Homologous Series of Chemical Compounds in Three-component Systems (Aa+ – Bb+ – Cc–) and (Zn2+ - Ge4+ - P3-) in Generalized Form
Chemistry受け取った 13 Nov 2023 受け入れられた 20 Nov 2023 オンラインで公開された 21 Nov 2023
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受け取った 13 Nov 2023 受け入れられた 20 Nov 2023 オンラインで公開された 21 Nov 2023
For the first time, a method for calculating formulas of homologous series of chemical compounds of the systems (Aa+ – Bb+ – Cc–) and {Zn2+ – Ge4+ – P3–} in a generalized form is presented. The calculation is confirmed by the literature experimentally obtained compounds: thirteen compounds of the system (Na+ – Ti4+ – O2–), seven – systems (Li+ – Ti4+ – O2–), five – systems (K+ – V5+ – – O2–), eight – systems (Ba2+ – Cu2+ – O2–). Homological series in (Aa+ – Bb+ – Cc–) have the following generalized form: A{t – k·r + nr – r)bcBracC{t – k·r + nr)ab and AtbcB{r – k·t + nt – t}acC (r – k·t + nt)ab.
In (Zn2+ – Ge4+ – P3–) systems for the m-group the formulas of homologous series, that develops towards Ge3P4, have the following generalized form: Zn6tGe(6r – 6kt + 6n – 6t)P(8r – 8kt + 8n) and for am-homologous series – Zn6Ge3nP4(n + 1). A method for calculating formulas of homologous series of chemical compounds in a generalized form can be used for any system of chemical elements.
The search for new Chemical Compounds (CC) in multicomponent systems of Chemical Elements (CE) is a difficult task. The great variety of properties of a set of Three-Component Chemical Compounds (TCC) is of great interest in solving a number of scientific and applied studies. There are known works in the literature that use the mathematical apparatus for predicting phases in multicomponent systems. Thus, semiempirical quantum-chemical methods, such as Hartree-Fock-Rutaan and Hartree-Fock-Slater methods [
- ], are used to calculate the formulae of hypothetical multicomponent CC. When using these methods to describe a chemical system, many physical and chemical phenomena must be taken into account. The exact solution of the basic laws leads to overcomplicated calculations. Therefore, for practically all CE systems, the solution of the corresponding electronic equations used in quantum-chemical calculations is only possible approximately. Well-known quantum-chemical methods of calculation, allow to calculate the formula of any CC, are rather complicated and require special knowledge in the field of mathematical programming.According to the works [
- ], knowledge of the laws of formation of Homological Series (HS) of chemical compounds can be included in the process of searching for new CC.Thus, the author of the work [8, p. 190] believes that “...the activated complex theory consists in the fact that in the course of any chemical reaction, the initial configuration of atoms passes to the final one as a result of continuous change of interatomic distances”, which is characterized by the formation of various critical intermediate configurations, i.e. activated complexes”. On the basis of this idea, in the works [
It is known [ , ] that multicomponent CE systems include CC, which are combined into different HS. As the HS develops, the fundamental properties of its members change in a regular way, which is determined by a regular change in the crystal structure of homologs [ - ]. In turn, the regular change in the crystal structure of homologs is determined by the regular change in their composition, which contributes to the search for new CC in [ - ]. In the works [ - ], the structural homology of inorganic CC of different systems of CE is discussed in detail.
So far, judging from the literature, the formulas of HS are known, which were obtained only empirically.
In the literature, there are known HS of systems with a single set of chemical elements:
BamCu2+m + nO [
]; or LanNinO3n – 1 [ ]; Lan + 1NinO3n + 1, n = 1-5 [ ]; Lan + 1NinO3n – 1, n = 7, 9, 13 and 30 [ ]; La2n – 4Ni2O4n – 5, n = 5-8 [ ]; or Fe2+nFe3+2mOn + 3m [ ] or Srn + 1TinO3n + 1[ ]. Thus, in the (Ba2+ – Cu2+ – O2–) system, the homologous series of CC is described by the formula BamCum + nO3n – 1, where 2m = 2n – 1 [ ], and in [ ] it is reported that a series of CC belonging to the HS were obtained, described by the formula nFeO∙mFe2O3 ≡ Fe2+nFe3+2mO2–n + 3m.Additionally, experimentally obtained inorganic CC described by formulas that exhibit regular changes in composition are known in the literature: MnO3n – 1 (M = Mo, W) [
], MnO2n – 1 (M = Ti, V) (n = 4-10) [ - ], WnO3n – 2 (n = 20, 38-40) [ ].However, in the case of “Magneli phases” in the systems (M – O), where M º Mo, W, V, Ti, [
- ] and in the system (La – Ni – O) [ - ], all these formulas, without taking into account the existence of atom of metal with the same name with different atom valence in them, in our opinion, they cannot be considered correct. Following the electron neutrality of CC formulas, in all crystal lattices of CC belonging to the “Magnéli phases” described by formulas from [ - ], two metal ions of the same name with different atom valence should be present: for example, M5+ and M6+ in MenO3n – 1 or in WnO3n – 2 (M º Mo, W), or M3+ and M4+ in MnO2n – 1 (M º Ti, V). In the formulas described in [ - ] two ions Ni2+ and Ni3+ with different atom valence should be present as equal chemical entities, determining the existence of the crystal lattice of CC. That is why the formulas of “Magnéli phases” from [ - ], in our opinion, should be attributed not to two-component, but to three-component CE systems. In turn, the formulas related to the (La – Ni – O) system [ - ] belong not to a three-component system but to a four-component CE system, (La3+ – Ni2+ – Ni3+). For this reason, the formulas from [ - ], in our opinion, could be written as follows:MenO3n – 1 º Me5+2Me6+n – 2O3n – 1, where (Me º Mo, W) and n = 8–12, 14 [
]; or MenO2n – 1 º Me3+2Me4+n – 2O2n – 1, where (Me º Ti, V) and n = 4-10 [ - ]; or WnO3n – 2 º W5+4W6+n – 4O3n – 2, where n = 20, 38-40 [ ], and the formulas from [ - ] are suggested to be written as follows: LanNinO3n – 1 [ ] º LanNi2+2Ni3+n – 2O3n – 1, Lan + 1NinO3n + 1 [ ] º Lan + 1Ni2+Ni3+n –1O3n + 1, Lan + 1NinO3n – 1 [ ] º Lan + 1Ni2+Ni3+n –1O3n – 1 and La2n – 4NinO4n – 5 [ ] º La2n – 4Ni2+n – 2Ni3+2O4n – 5.In the literature, for the system (M+ – Ti4+ – O2–), where M+ º Li+, Na+, K+, Rb+, Cs+, a series of formulas for experimentally obtained TCC is known, generalized for n = 1-9 in the form of M+4Ti4+nO2(n + 1) [
].The aim of this study is to develop a method for calculating the formulas of a homologous series of three-component systems of chemical elements in a generalized form using the geometric features of the triangle representing the system of chemical element ions.
The method for calculating HS of three-component systems developed in [
- ] allows, in our opinion, for the generalized determination of HS formulas. This conclusion is drawn from the findings presented in [ , ], which provide numerous confirmations of the accuracy of the HS calculation method for a range of three-component systems through experimental results taken from the literature. It should be noted, however, that the laws governing the formation of individual CC and the laws governing the formation of HS are different. Before the publications of [ - ], there was no possibility in the literature to predict the formation scheme of HS. In some cases, HS formulas were only experimentally determined in works [ - ].Based on the works [
- ], the justification for the generalized method of calculating HS can be formulated as follows:1) In our view, the rule (or scheme) for forming HS of chemical compounds can be formulated by considering all possible directions of chemical interactions between the components of the system, as allowed by the combination of the valence electron count of chemical elements and the composition of complex atomic clusters in the system. In reality, only ions of elementary substances and “certain intermediate atom configurations critical for a given reaction” participate in chemical interactions [
]. In our case, these are activated CC and charge clusters (ChCl). It is clear that determining the formula of HS is possible if, among the many presumed directions of chemical interaction between the components of the CE system, we can select those responsible for the formation of HS. Therefore, to solve this problem, the CE system must be represented as ions, as only ions can chemically interact with each other, producing intermediate, more complex, compositionally charged clusters and activated multi-component CC. To do this, the system is represented as a triangle (Figures 1-3), with CE ions placed at its vertices.2) It was found that the geometric features of the triangle representing the system of CE ions consist of representing the reaction of the interaction between any pair of reacting system components as a line segment, where each pair of reactants and the product of their interaction lie on a line segment unique to them. In cases where line segments connecting different pairs of chemically interacting system components intersect at a single point, the common product of the interaction, ChCl or activated CC, must be located at that point. This feature is explained by the difference in the laws governing the interaction of different pairs of reactants, which are determined by the different combinations of valence ions of CE and the composition of interacting pairs of reactants represented by different line segments: at the point of intersection of these line segments, different laws of chemical interaction of different pairs of chemical entities cannot coexist simultaneously.
Thus, the calculation of HS formulas, i.e., the search for new HS homologs, is based on the premise that homologs are located within a triangle at the intersection of line segments connecting different pairs of chemically interacting components of the system, including ions, CC and ChCl.
3) Next, we will consider that homologs enriched with the two-component CC (TwCC), AcCa, belong to the p-groups of HS, while homologs enriched with the BcCb cluster belong to the m-groups of HS – Figure 1-3. HS are formed depending on the direction of development through a chain of sequentially occurring interactions of TCC with cation Aa+ – the development direction of p-groups of HS is AcCa. When TCC interacts with cation Bb+ – the m-groups of HS develop towards BcCb.
The formation of HS involves three-component charge clusters (TChCln) through interaction with anion Сс– (Figures 1-3).
The formation of HS is described by the following scheme:
TChCl n = 1 + Cc- ® TCC n = 1, TCC n = 1 + Aa+ (or Bb+) ® TChCl n = 2, TChCl n = 2 + Cc- ® TCC n = 2, TCC n = 2 + Aa+ (or Bb+) ® TChCl n = 3, TChCl n = 3 + Cc- ® TCC n = 3…………………………….(1)
In the text, the determined formulas of CC and ChCl as reactants and products of their interaction are highlighted in bold. The value of n is determined experimentally, where n represents the position of the homolog in HS, (1 ≤ n).
4) Activated ТХСn are located on line segments (AcCa – BcCb) – Figures 1-3. In works [
- ], the nature of the connection of the same TCCn, which simultaneously belongs to both the p-groups and m-groups of HS, is described. Following the conditions outlined in paragraph 3 regarding the membership of TCC in p-groups and m-groups of HS, it can be concluded that in the case of p-groups of HS, its first homologs, TCCn = 1, are located on the line segment (p. 2 – BcCb), excluding BcCb, and the clusters TCCn > 1 are located on the line segment (p. 2 – AcCa), excluding point 2 and AcCa (Figures 1,2).In the case where the same TCCn cluster belongs to the m-group of HS, its first homologs, TCCn = 1, are located on the line segment (p. 2 – AcCa), excluding AcCa. The clusters TCCn > 1 are located on the line segment (p. 2 – BcCb), excluding p. 2 and BcCb (Figures 1,3).
5) Clusters TChCln = 1, belonging to p-groups of HS, are located on the line segment (p. 1 – Bb+), excluding Bb+, and clusters TChCln > 1 are located on the line segment (p, 1 – AcCa), excluding p. 1 and AcCa – Figures 1,2. In the text and in Figure 1, the following notations are used: p. 1 º point 1, p. 2 º point 2, p. 3 º point 3, and so on.
In the case where the TChCln cluster belongs to the m-group of HS, its first homologs, TChCln = 1, are located on the line segment (p. 1 – Aa+), excluding Aa+, and clusters TChCln > 1 are located on the line segment (p, 1 – BcCb), excluding p. 1 and BcCb (Figures 1,3).
6) TCCn and TChCln, occupying the same position in the same HS, are linked by the reaction:
TChCln + Сс– ® TCCn……………………….......……………………(2)
7) Any known TCC is necessarily a member of some HS.
8) Any HS consists of a CC branch and a ChCl branch, the members of which are linked by reaction (2). Each branch of the same HS develops towards enrichment with only one Two-component CC (TwCC), either AcCa or BcCb.
9) The geometric features of the triangle, if following scheme (1), ensure a systematic and periodic The geometric features of the triangle, if following scheme (1), ensure a systematic and periodic change in the composition of homologs in HS.
10) The difference in compositions, ∆, of any adjacent homologs in the same HS is constant:
∆m(p) = TCCn + 1 – TCCn = TChCln + 1 – TChCln ........................,.(3)
11) The charges of all ChCl in the same HS are identical.
12) In the case of determining the formulas of HS to which some known (basic) TCCn(bas) belongs, the calculation of HS formulas is carried out as follows: first, the formulas of TChCln(bas), TCCn(bas) + 1, and TChCln(bas) + 1 are calculated, then the formulas of ∆ and the first terms, TCCn = 1 and TChCln = 1, of the considered HS are determined. Formulas TCCn = 1 and TChCln = 1 are calculated by subtracting the maximum number of times the formula ∆m(p) from the formulas of basic clusters while retaining the minimum number of the cation contained in the formula ∆m(p) in their composition:
TCCn(bas) – k∙∆m(p) = TCCn = 1…………...………………………. (4)
TChCln(bas) – k∙∆m(p) = TChCln = 1…...……….......................(5)
where (0 ≤ k). If k = 0, then n(bas) = 1.
13) The formula of any homolog in the same HS, i.e., the formula of the HS, is determined as follows:
CC branch: TCCn = 1 + (n – 1)·∆m(p) = TCCn..………………(6)
ChCl branch: TChCln = 1 + (n – 1)·∆m(p) = TChCln….…….(7)
14) When calculating HS, it should be taken into account that one of the CE may have different valencies, being not only a component that does not introduce impurities into the crystalline lattice of TCC but also one of the main CE in the crystalline lattice.
In practice, researchers often need to determine the formulas of HS to which a known TCCn(bas) already belongs. In the formation of these HS, any TCCn can participate, including TCCn = 1 and TCCn > 1.
Let’s examine the sequentially occurring chemical reactions in a three-component system.
The formation of HS occurs according to scheme (1). The system (Aa+ – Bb+ – Cc–) is initially in a state where the interaction of a positively charged ion with an anion will lead to the formation of activated TwCC, AcCa, and BcCb (Figure 1).
cAa+ + aCc- = AcCa…………………………………………………. (8)
cBb+ + bCc- = BcCb…………………………………………………. (9)
Activated TwCC, AcCa and BcCb can interact with each other to form TCCn based on the ratios of ions Aa+, Bb+ and Cc- in TCCn based on the ratios of ions Aa+, Bb+ and Cc- in TChCln, which participate in reaction (2):
x∙AcCa + y∙BcCb = (AxcBycC(x + y)ab = TCCn)0………………...(10)
Furthermore, according to the initial ratios of ions in TCCn and TChCln, the interaction of positively charged ions with each other leads to the formation of two-component charged clusters (TwChCln), which are connected to TCCn and TChCln by reaction (2), where (1 ≤ n):
x∙Aa+ + y∙Bb+ = ([AxbBya](x + y)ab+ = TwChCln)……………... (11)
The combined interaction of (TChCln = 1 = p. 1) and TwChCln = 1 with anion Cc- according to (2), as well as activated AcCa and BcCb with each other leads to the formation of a cluster of (TCCn = 1 = p. 1) – Figure 1. Thus, the clusters (TChCln = 1 = p. 1), (TwChCln = 1 = p. 3) and (TCCn = 1 = p. 2) turn out to be the founders of two groups of HS, αm-group and αp-group, since (TChCln = 1 = p. 1) and (TCCn = 1 = p. 2) can interact with both Bb+ and Aa+, respectively. The interactions mentioned are characterized by the intersection of segments corresponding to the reacting components of the CE system. Thus, the formation of different clusters TChCln are characterized by the intersection of segments (AcCa – Bb+) and (BcCb – Aa+), and the formation of cluster TCCn is characterized by the intersection of segments (TChCln – Cc–), (Aa+ – Bb+) and (AcCa – BcCb), which is described by the following reaction equations in the formation of the αm-group of HS and αp-group of HS (Figure 1).
bAcCa + acBb+ = aBcCb + bAa+ = ([AbcBacCab]abc+ = TChCln = 1 = p. 1)………………………….(12)
([AbcBacCab]abc+ = TChCln = 1 = p. 1) + abCc- = {bcAa+ + acBb+ = ([AbcBac]2abc+ =TwChCln = 1 = p. 3) + 2abCc- = bAcCa + aBcCb = (AbcBacC2ab = TCCn = 1 = p. 2)…………………………….(13)
Calculation of the formula for αp-HS developing towards AcCa: The continuous nature of the chemical interaction of the components of the system (Aa+ – Bb+ – Cc-) and the formation of HS implies that the formation of p-groups of HS is described by the interaction of TCCn with Aa+. The interaction of TChCln and TwChCln with Cc- is characterized by the intersection of segments (TCCn – Aa+) and (Bb+ – AcCa) at the point corresponding to TChCln + 1, including the intersection of segments (TCCn + 1 – Cc-) and (TwChCln – Cc-) with the segment (AcCa – BcCb) at the point corresponding to TCCn + 1 – Figure 1. In turn, clusters (AbcBacC2ab = TCCn = 1 = p. 2) interact with Aa+, and activated AcCa reacting with Bb+ to form (TChCln = 2=p. 4), and clusters (TwChCln + 1 = p. 6) and (TChCln + 1 = p. 4) interact with Cc- and form (TCCn + 1 = p. 5) – Figure 1. These interactions begin to form αp-HS, the members of which, as this HS develops, are enriched with the AcCa component, which for αp-HS is described by the reaction equation (Figure 1).
(AbcBacC2ab = TCCn = 1 = p. 2) + bcAa+ = acBb+ + 2bAcCa = ([A2bcBacC2ab]abc+ = TChCln = 2 = p. 4).…..............................(14)
([A2bcBacC2ab]abc+ = TChCln = 2 = p. 4) + abCc- = {2bcAa+ + acBb+ = ([A2bcBac]3abc+ = TwChCln = 2 = p. 6)} = 2bAcCa + aBcCb = aBcCb = (A2bcB2acC3ab = TCCn = 2 = p. 5)……………………….(15)
According to (3), (6) and (7) the formula ∆αp is determined as follows:
∆αp = (A2bcBacC3ab = TCCn = 2 = p. 5) – (AbcBacC2ab= TCCn = 1 = p. 2) = [A2bcBacC2ab]abc+ =TChCln = 2 = p. 4) – ([AbcBacCab]abc+ = TChCln = 1 = p. 1) = AbcCab…………………………………………(16)
Knowledge of the formulas of the first homologs (TCCn = 1 = p. 2), (TChCln = 1 = p. 1), and ∆αp allows us to determine the formulas of both branches of αp-HS:
CC branch in αp-HS: (AbcBacC2ab= TCCn = 1 = p. 2) + (n – 1)AbcCab = AnbcBacC(n + 1)ab ………..............................................(17)
ChCl branch in αp-HS: ([AbcBacCab]abc+ = TChCln = 1 = p. 1) + (n – 1)AbcCab = [AnbcBacCnab]abc+…………………………………...(18)
The formulas for both branches of HS in other p-group HS are determined in accordance with dependencies (4)-(7).
Calculation of the formula for αm-HS developing towards BcCb: In the case where the cluster (TCCn = 1 = p. 2) reacts with cation Bb+ to form (TChCln = 2 = p. 7), and cluster (TChCln = 2 = p. 7) reacts with anion Cc-, and to form (TCCn = 2 = p. 8) but they participate in the formation of the αm-group of HS (Figure 1).
(AbcBacC2ab = TCCn = 1 = p. 2) + acBb+ = bcAa+ + 2aBcCb = ([AbcB2acC2ab]abc+ = TChCln = 2 = p. 7)……………………………..(19)
([AbcB2acC2ab]abc+ = TChCln = 2 = p. 7) + abCc- = {2bcAa+ + acBb+ = ([AbcB2ac]3abc+ = TwChCln = 2 = p. 9) + 2abCc- = bAcCa + 2aBcCb = aBcCb = (AbcB2acC3ab = TCCn = 2 = p. 8)…………….(20)
According to (3), (6), and (7) the formula ∆αm, TCCn, and TChCln are determined by the formulas of both branches of αm-HS:
∆αm = (AbcB2acC3ab = TCCn = 2 = p. 5) – (AbcBacC2ab= TCCn = 1 = p. 2) = [AbcB2acC2ab]abc+ = TChCln = 2 = p. 4) – ([AbcBacCab]abc+ = TChCln = 1 = p. 1) = BacCab……..........………………………(21)
CC branch in αm-HS: (AbcBacC2ab= TCCn = 1 = p. 2) + (n – 1)BacCab = AbcBnacC(n + 1)ab ………..............................................(22)
ChCl branch in αm-HS: ([AbcBacCab]abc+ =TChCln = 1 = p. 1) + (n – 1)BacCab = [AbcBnacCnab]abc+…………………………………(23)
The formulas for both branches of HS in other m-group HS are determined in accordance with dependencies (4)-(7).
Calculation of the generalized formula for homologous series to which a known (Basic) TCCn(bas) belong: In the process of designing various devices, researchers often face the task of determining the formulas of TCC that would possess more suitable properties compared to the currently used TCC in the device. In situations where the composition of the utilized TCC is known and experimentally confirmed, we will consider this cluster as the basic one TCCn(bas). The problem of finding new TCCn ≠ n(bas) can be solved by identifying the formulas of HS to which the basic TCCn(bas) belongs. In the desired HS, the fundamental properties of homologs, including TCCn(bas), change periodically and systematically [
, ]. To determine the regularity of HS formation in a generalized form, it is necessary to represent the formula of TCCn(bas) appropriately. Thus, the formula of any TCC, including TCCn(bas), can be expressed in a generalized form as follows:tAcCa + rBcCb = AtbcBracC(t + r)ab…………………………………(24)
Where (0 < t, r).
Calculation of the generalized formula for the p-Group of ГС to which a known (Basic) (TCCn(bas) = AtbcBracC(t + r)ab) belongs: In accordance with paragraths 3-5, the basic cluster, represented in a generalized form as (AtbcBracC(t + r)ab = TCCn(bas)), begins to form the p-group of HS by interacting with Aa+. In this case, the formulas of TChCln(bas) and TwChCln(bas), associated with TCCn(bas) by reaction (2), are determined by the intersection of segments {((AtbcBracC(t + r)ab = TCCn(bas) = p. 10) – p. 12) – Aa+}, and {(TwChCln(bas) = p. 12) – Cc-} and (Bb+ – AcCa), which is described by the reaction equation (Figure 2).
{racBb+ + tbAcCa = ([AtbcBracCtab]rabc+ = TChCln(bas) = p. 11)} + rabCc– = {tbcAa+ + racBb+ = ([AtbcBrac](t + r)abc+ = TwChCln(bas)) = p. 12} + (t + r)abCc– = (AtbcBracC(t + r)ab = TCCn(bas) = p. 10).....(25)
The initiation of the formation of the p-group of HS based on (AtbcBracC(t + r)ab = TCCn(bas) = p. 10) is characterized by the intersection of segments (TCCn(bas) – Aa+), and (Bb+ – AcCa) at a point corresponding to (TChCln(bas) + 1 = p. 13), as well as the intersection of segments {(TChCln(bas) + 1 = p. 13) – Сс–} and {(TwChCln(bas) + 1 = p. 12) – Сс–} with the segment (AcCa – BcCb) at a point corresponding to (TCCn(bas) + 1 = p. 14), which is described by the reaction equations (Figure 2).
(AtbcBracC(t + r)ab = TCCn(bas) = 1 = p.10) + rbcAa+ = racBb+ + (t + r)
bAcCa = ([A(t + r)bcBracC(t + r)ab]rabc+ = TChCln(bas) + 1) = p. 13)….(26)
([A(t + r)bcBracC(t + r)ab]rabc+ = TChCln(bas) + 1 = p. 13) + rabCc– = (t + r)bAcCa + raBcCb = {(t + r)bcAa+ + racBb+ = (TwChCln(bas) + 1 = [A(t + r)bcBrac](t + 2r)abc+ = p. 15)} + (t + 2r)abCc- = (A(t + r)bcBracC(t + 2r)ab = TCCn(bas) + 1 = p. 14)..……………....................(27)
The formula Δp, TCCn = 1 and TChCln = 1 for the p-group of HS is determined according to (3)-(5), (25)-(27):
Δp = (A(t + r)bcBracC(t + 2r)ab = TCCn(bas) + 1 = p. 14) – (AtbcBracC(t + r)ab = TCCn(bas) = p. 10) = ([A(t + r)bcBracC(t + r)ab]rabc+ = TChCln(bas) + 1 = p. 13) – ([AtbcBracCrab]tabc+ = TChCln(bas) = p. 11) = ArbcCrab .................(28)
TCCn = 1 = (AtbcBracC(t + r)ab= TCCn(bas) = p. 10) – k·ArbcCrab = A(t – k·r)bcBracC(t + r – k·r))ab…….…...(29)
TChCln = 1 = ([AtbcBracCtab]rabc+ = TChCln(bas) = p. 11) – k·ArbcCrab =[A(t – k·r)bcBracC(t –k·r)ab]rabc+......……………………….....………...(30)
Where (0 ≤ k) and k characterizes the positioning of TCCn(bas) in HS, and for αp-HS corresponds n(bas) = 1 and k = 0.
As can be seen, the determination of the composition of the first homologs and the formulas of both branches of the sought p-group of HS according to the formulas (29), (30), (6), and (7) depends on the relationship between the values t and k·r. In this case, two variants are possible:
1) Inequality (t ≤ k·r) when (t, r, k > 0) does not allow obtaining formulas for TCCn = 1 and TChCln = 1 according to (29) and (30) by subtracting the product (k·Δp º k·ArbcCrab) from the formulas (AtbcBracC(t + r)ab = TCCn(bas) = p. 10) and ([AtbcBracCtab]rabc+ = TChClnbas) = p.11). It follows that (k = 0) and n(bas) = 1. This fast indicates that when (t ≤ k·r), the basic cluster is the first homolog (AtbcBracC(t + r)ab = TCCn(bas) = 1 = p. 10) in this p-group of HS. Therefore, any homologue or both branches of the desired p-group of HS is determined according to (6), (7), and (28):
CC branch in p-group of HS – (AtbcBracC(t + r)ab = TCCn(bas) = 1 = p. 10) + (n – 1)ArbcCrab = A{t + r(n – 1)}bcBracC{t + rn}ab…............(31)
ChCl branch in p-group of HS – ([AtbcBracCtab]rabc+ = TChCln(bas) = 1 = p. 11) + (n – 1)ArbcCrab = [A{t + r(n – 1)}bcBracC{t + r(n – 1)}ab]rabc+…………............................................................(32)
2) In the case when the inequality (k·r < t) holds, to determine the composition of the first homologs, it is possible to subtract the product (k·∆p º k·ArbcCrab) from the formulas of the basic clusters (AtbcBracC(t + r)ab = TCCn(bas) = p. 10) and ([AtbcBracCtab]rabc+ = TChCln(bas) = p. 11), i.e. at (0 < k) and {n(bas) > 1}. Then the first members of TCCn = 1 and TChCln = 1 of the sought p-group of HS will be determined by expressions (29) and (30). Any homologue or both branches of the p- p-group of HS will be determined according to (6), (7), (28), (29), and (30):
CC branch in p-group of HS – (A(t – k·r)bcBracC(t + r – k·r))ab = TCCn = 1) + (n – 1)ArbcCrab = A{t – k·r + (n – 1)r}bcBracC{t – k·r + nr}ab....(33)
ChCl branch in p-group of HS – ([A(t – k·r)bcBracC(t – k·r)ab]rabc+= TChCln = 1) + (n – 1)ArbcCrab = [A {t – k·r + (n – 1)r}bcBracC{t – k·r + (n – 1)r}ab]rabc+….........………………….……………………………….(34)
It should be noted that for the p-group of HS in both cases (t ≤ k·r) and (kr < t) cluster TCCn = 1 is located in the p. 2, and cluster TCCn(bas) > 1 should be on the segment (p. 2 – AcCa) excluding p. 2 and AcCa. Cluster TChCln = 1 is located in the on the segment (p. 1 – Bb+) excluding p. 1 and cluster TCCn(bas) > 1 should be on the segment (p. 1 – AcCa) excluding p. 1 and AcCa (Figure 2).
Comparing the concentration coefficients for Aa+ in the formula of the base cluster (AtbcBracC(t + r)ab = TCCn(bas) = p. 10) and in the formula of the homologue in the p-group HS in the generalized form At – k·r + {n(bas) – 1)r}bcBracC{t – k·r + n(bas)∙r}ab from (33), it can be seen that there is equality {rn(bas) – r – k·r} = 0 holds. Then for (r ≠ 0) we get:
k = {n(bas) – 1}..…………………………………………………(35)
In reality, the value of k is determined during the calculation of the p-group HS in accordance with the possibility of subtracting the product (k·∆p º k·ArbcCrab) from the formula {AtbcBracC(t + r)ab = TCCn(bas)}: k·r and t are compared. The values of t and r are determined by the formula TCCn(bas). By setting the value of n, it is possible, in accordance with the formulas (AtbcBracC(t + r)ab = TCCn(bas) = p. 10), (33) and (35), to calculate the formula of any homologue of TCCn belonging to the p-group of HS.
Calculation of the generalized formula for the m-group of hs to which the known (basic) (TCCn(bas) = AtbcBracC(t + r)ab)
belongs: Let the cluster TCCn(bas), the formula of which is represented in a generalized form as (AtbcBracC(t +r)ab = TCCn(bas) = p. 19), interact with Bb+ to start forming the HS, which in this case will belong to the m-group of HS. In this process, the formulas for (TChCln(bas) = p. 20) and (TwChCln(bas) = p. 21) related to TCCn(bas) by reaction (2) are determined by the composition of TCCn(bas), which is described by the reaction equation:
{tbcAa+ + racBb+ = ([AtbcBrac](t + r)abc+ = TwChCln(bas) = p. 21)} + (t + r)abCc- = {tbcAa+ + raBcCb = ([AtbcBracCrab]tabc+ = TChCln(bas) = p. 20) + tabCc– = (AtbcBracC(t + r)ab = TCCn(bas) = p. 19)……(36)
The formation of the m-group of HS based on (AtbcBracC(t + r)ab = TCCn(bas) = p. 19) is characterized by the intersection of the segments (TCCn(bas) – Bb+) and (Aa+ – BcCb) at the point corresponding to (TChCln(bas) + 1 = p. 22), as well as the intersection of the segments {(TChCln(bas) + 1 = p. 22) – Сс-} and {(TwChCln(bas) + 1 = p. 24) – Сс-} with the segment (AcCa – BcCb) at the point corresponding to (TCCn(bas) + 1 = p. 23) – Figure 3, which is described by the following reaction equations:
(AtbcBracC(t + r)ab = TCCn(bas) = 1 = p.19) + tacBb+ = tbcAa+ + (t + r)aBcCb = ([AtbcB(t + r)acC(t + r)ab]tabc+ = TChCln(bas) + 1 = 2 = p.22)………………..…………………………(37)
([AtbcB(t + r)acC(t + r)ab]tabc+ = TChCln(bas) + 1 = 2 = p.22) + tabCc– = tbAcCa + (t + r)aBcCb = {tbcAa+ + (t + r)acBb+ = (TwChCln(bas) + 1 = 2 = [AtbcB(t + r)ac](2t + r)abc+ = p. 24)} + (t + r)abCc- = (AtbcB(t + r)acC(2t + r)ab = TCCn(bas) + 1 = 2 = p. 23)….……………………...........(38)
The formula Δm, TCCn = 1, and TChCln = 1 are determined according to (3), (4), (5), (36)-(38):
Δm = (AtbcB(t + r)acC(2t + r)ab = TCCn(bas) + 1) – (AtbcBracC(t + r)ab = TCCn(bas)) = ([AtbcB(t + r)acC(t + r)ab]tabc+ = TChCln(bas) + 1 = TChCln = 2) – ([AtbcBracCrab]tabc+ = TChCln(bas)) = BtacCt…………………...(39)
TCCn = 1 = (AtbcBracC(t +r)ab= TCCn(bas) = p. 19) – k·BtacCtab = AtbcB(r – k·t)acC(t + r – k·t))ab.………….(40)
TChCln = 1= ([AtbcBracCrab]tabc+ = TChClnbas) = p. 20) – k·BtacCtab = [AtbcB(r – k·t)acC(r – k·t)ab]tabc+…(41)
As can be seen from equations (40) and (41), determining the composition of the first homologs and formulas of both branches of the sought m-group of HS depends on the relationship between the values of r and k·t. In this regard, two variants are possible:
1) In the case of the inequality (r ≤ k·t) with {0 < t, r, k}, it is not possible to obtain the compositions of TCCn = 1 and TChCln = 1 according to (4) and (5) by subtracting the formula (Δm = BtacCtab) from the formulas (AtbcBracC(t + r)ab = TCCn(bas) = p. 19) and ([AtbcBracCrab]tabc+ = TChCln(bas) = p. 20). In this scenario, it implies that (k = 0), and {n(bas) = 1}. Consequently, both branches of the m-group of HS can be determined according to (6), (7), and (39)-(41):
CC branch of m-group of HS – (AtbcBracC(t + r)ab = TCCn(bas) = 1 = p. 19) + (n – 1)BtacCtab = AtbcB{r + t(n – 1)}acC{r + tn}ab……....(42)
ChCl branch of m-group of HS – ([AtbcBracCrab]tabc+ = TChCln(bas) = 1 = p. 20) + (n – 1)BtacCtab = [AtbcB{r + t(n – 1)}acC{r + t(n – 1)}ab]tabc+………….............................................................(43)
2) In the case of the inequality (k·t < r), to determine the formulas of the first homologs, it is possible to subtract the product (k·∆m º k·BtacCtab) from the composition of the basic clusters (AtbcBracC(t +r)ab = TCCn(bas) = p. 19) and ([AtbcBracCrab]tabc+ = TChCln(bas) = 1 = p. 20), i.e., (0 < k). In this scenario, the first members of the sought m-group of HS will be determined by equations (37) and (38). Both branches of the m-group of HS will be determined according to (6), (7), (36), (37), and (38):
CC branch of m-group of HS – AtbcB{r – k·t}acC{t + r – k·t}ab = TCCn = 1) + (n –1)BtacCtab = AtbcB{r – kt + (n – 1)t}acC{r – k·t + nt}ab ….(44)
ChCl branch of m-group of HS – ([AtbcB(r – k·t)acC(r–k·t)ab]tabc+= TChCln = 1) + (n – 1)BtacCtab = [AtbcB{r – k·t + (n – 1)t}acC{r – k·t + (n – 1)t}ab]tabc+…………………………………………………….........….(45)
It should be noted that for the m-group of HS in both cases (r ≤ k·t) and (k·t < r) cluster TCCn = 1 is located in the p. 2, and cluster TCCn(bas) > 1 should be on the segment (p. 2 – BcCb) excluding p. 2 and BcCb. Cluster TChCln = 1 is located in the on the segment (p. 1 – Aa+) excluding p. 1 and cluster TCCn(bas) > 1 should be on the segment (p. 1 – BcCb) excluding p. 1 and BcCb (Figure 3).
Comparing the concentration coefficients for Bb+ in the formula of the base cluster (AtbcBracC(t + r)ab = TCCn(bas) = p. 19) and in the formula of the homologue in the m-group HS in the generalized form AtbcB{r – kt + (n – 1)t}acC{r – k·t + nt}ab from (44), it can be seen that there is equality {t∙n(bas) – t – k·t = 0} holds. Then for (t ≠ 0) we get:
{k = {n(bas) – 1}……………………………………....…………(46)
In reality, the value of k is determined during the calculation of the m-group HS in accordance with the possibility of subtracting the product (k·∆m º k·ArbcCrab) from the formula {AtbcBracC(t + r)ab = TCCn(bas)}: k·t and r are compared. The values of t and r are determined by the formula TCCn(bas). By setting the value of n, it is possible, in accordance with the formulas (AtbcBracC(t + r)ab = TCCn(bas) = p. 19), (44), and (45), to calculate the formula of any homologue of TCCn belonging to the m-group of HS.
Calculation of the generalized formula for the m-group of HS developing towards Ge3P4 in the system (Zn2+ - Ge4+ - P3-) to which the known (basic) (TCCn(bas) = ZnGeP2) belongs:
As an example of the practical application of the above HS formulas in a generalized form, we calculate the formula of the m-group of HS, which belongs to the well-known (basic) (TCCn(bas) = ZnGeP2 º AtbcBracC(t + r)ab). Attention to the system (Zn2+ – Ge4+ – P3-) and, in particular, to ZnGeP2 is caused by the fact that the ZnGeP2 compound, having a chalcopyrite crystal structure, has highly effective nonlinear optical characteristics that are used for parametric conversion of medium and far infrared radiation range, as well as for terahertz radiation [
]. The calculated HS formula based on (TCCn(bas) = ZnGeP2) will allow us to determine the formulas of other unknown TCC-homologues that may be potential substitutes for the compound ZnGeP2.When solving this problem, we agree that homologues, as they develop m-HS, enriched by a cluster (Ge3P4 º BcCb).
So, for (TCCn(bas) = ZnGeP2 º AtbcBracC(t + r)ab) we get: Aa+ º Zn2+, Bb+ º Ge4+, Cc– º P3–, bc = 12, ac = 6, ab = 8, abc = 24, tbc = 1, t = 1/12, rac = 1, r = 1/6, (t + r)ab = 2, (t + r) = 2/8. Then the following is true:
(ТCСn(bas) = AtbcBracC(t +r)ab º ZnGeP2 º Zn12/12Ge6/6P16/8)...(47)
In order to determine the position of the base cluster in the HS m-group, it is necessary to determine the formula Δm (direction Ge3P4) in accordance with (39):
Δm = BtacCtab = Ge6tP8t º Ge6/12P8/12………………………… (48)
To determine the value of k, it is necessary to compare the formula (Δm = Ge6/12P8/12) with the cluster formula (TCCn(bas) = Zn12/12Ge6/6P16/8) from (47): when comparing, it can be seen that (r = = 1/6) > (t = 1/12). Therefore, the formula {Δm = Ge6/12P8/12} from the formula (TCCn(bas) = Zn12/12Ge6/6P16/8) can be subtracted only once. In this case (k = 1) and {n(bass) = 2}. Then we get the formula TCCn = 1 according to (40):
(ТCСn = 1 = AtbcB(r – k·t)acC(t + r – k·t))ab = Zn12/12Ge6/12P16/12 º Zn6Ge3P8)
........(49)
The CC branch of the m-group of HS, to which ZnGeP2 belongs, can be represented as follows:
The branch of the CC m-group is AtbcB{r – k∙t + (n – 1)t}acC{r – k∙t + nt}ab º Zn12tGe3(n∙t – t + r – t∙k)P8{(n∙t + r – t∙k} º Zn12/12Ge(3n + 3 – 3k)/12P(8n + 16 – 8k)/12 º Zn6Ge3nP(n + 1) .........................................................(50)
Since the compound experimentally obtained in [
] (TCCn = 2 = ZnGeP2) in the desired HS m-group turned out to be the second member, given the continuity of the HS cluster (Zn6Ge3P8 = TCCn = 1) must exist. As can be seen, the relative germanium content in the cluster (TCCn = 1 = Zn6Ge3P8) is less than in the cluster (TCCn = 2 = ZnGeP2), which in the synthesis of Zn6Ge3P8 can give some advantages over ZnGeP2 while preserving the basic nonlinear optical characteristics of the material.According to (19), the formula of the first homologue (TCCn = 1 = p. 2 = AbcBacC2ab = Zn12Ge6P16) in αm-HS and the formula (TCCn = 1= AtbcB(r – k∙t)acC(t + r – k∙t))ab = Zn12/12Ge6/12P16/12 º Zn12Ge6P16 º Zn6Ge3P8) coincide, which indicates that formula (50) belongs to the CC branch of the αm-HS, and the base cluster (ZnGeP2 = TCCn(bas) = 2) belongs to the αm-HS.
Comparison of experiments (known from the literature) with the results of the calculation of HS
The operability of the method of calculating the HS of chemical compounds presented here and in [
]-[ ] is confirmed by numerous experiments taken from the literature [ ]: so, if in formula (25), AbcBnacC(n + 1)ab, replace Aa+ º Li+, Na+, K+, Rb+, etc., Bb+ º Ti4+, Cc– º O2–, then for the systems (Na+ – Ti4+– O2–) and (Li+ – Ti4+– O2–), the following can be obtained:1) Thirteen experimentally obtained compounds of the system (Na+ –Ti4+– O2–): n = 1 [
, ], 2 [ , ], 3 [ , ], 4 [ , , ], 5 [ , ], 6 [ , ], 7 [ ], 8 [ ], 9 [ ], 12 [27-29,32,], 14 [ ], 16 [ ], 18 [ , ].2) Seven compounds of the system (Li+ – Ti4+ – O2–) obey the calculated formula (22) (direction of development of HS – TiO2) – Li4Ti4+nO2(n + 1): n = 1 [
, , ], 2 [ ], 3 [ ], 4 [ ], 5 [ - ], 6 [ , ], 7 [ ], 8 [ , , ], 12 [ ]. Based on the calculations of the systems (Li+ – Ti4+ – O2–) and (Na+ – Ti4+ – O2–), formula (22) can be written for the system (M+ – Ti4+ – O2–), where M+ º Li+, Na+, K+, Rb+, so:M+4Ti4+nO2(n + 1)……………....…………………………………… (51)
The formula (51) obtained here completely coincides with the formula obtained in [
] only on the basis of experiment.3) When replacing Aa+ º K+, Bb+ º V5+ and Cc– º O2– five compounds of the system (K+ – V5+ – O2–) obey the calculated formula (22) (direction of development of HS – V2O5): K10V5+2nO5(n + 1): n = 3, 5, 15, 20, 25 [
, , ];4) When replacing Aa+ º Ba2+, Bb+ º Cu2+ and Cc– º O2– five compounds of the system (Ba2+ – Cu2+ – O2–) obey the calculated formula (22) (direction of development of HS – CuO) – BaCu2+nOn + 1: n = 1 [
, ], n = 2 [ ]; n = 3, 7 [ ]; n = 4 [ ];5) When replacing Aa+ º Ba2+, Bb+ º Cu2+ and Cc– º O2– three compounds of the system (Ba2+ – Cu2+ – O2–) obey the calculated formula (17) (direction of development of HS – BaO) – BanCu2+On + 1: n = 1 [
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Undalov Yu K. Homologous Series of Chemical Compounds in Three-component Systems (Aa+ – Bb+ – Cc–) and (Zn2+ - Ge4+ - P3-) in Generalized Form. IgMin Res. Nov 21, 2023; 1(1): 060-069. IgMin ID: igmin117; DOI: 10.61927/igmin117; Available at: www.igminresearch.com/articles/pdf/igmin117.pdf
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Ioffe Institute of the Russian Federation Academy of Sciences, Saint-Petersburg, Russia
Address Correspondence:
Undalov Yu K, Ioffe Institute of the Russian Federation Academy of Sciences, Saint-Petersburg, Russia, Email: undal@yandex.ru
How to cite this article:
Undalov Yu K. Homologous Series of Chemical Compounds in Three-component Systems (Aa+ – Bb+ – Cc–) and (Zn2+ - Ge4+ - P3-) in Generalized Form. IgMin Res. Nov 21, 2023; 1(1): 060-069. IgMin ID: igmin117; DOI: 10.61927/igmin117; Available at: www.igminresearch.com/articles/pdf/igmin117.pdf
Copyright: © 2023 Undalov Yu K. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Fok VA. The beginning of quantum mechanics. Science. 1976.
Roothaan CCJ. Rev. Mod. Phys. 1951; 23:2; 69. DOI:10.1103/RevModPhys.23.69
Slater JC. Phys. Rev. 1051; 51:3;385. https://doi.org/10.1103/PhysRev81.385
Undalov YK. Russian. Inorganic Chemistry. 1998; 43:1447.
Undalov YK. Russian. Inorganic Chemistry. 1999; 44:1315.
Undalov YK. Russian. Inorganic Chemistry. 1999; 44:1479.
Undalov YК, Terukov EI, Agafonov DV. Izvestia of St. Petersburg State Institute of Technology (Technical University). 2021; 59(85):26. DOI:10.36807/1998-9849-2021-59-85-26-36
Eriemin EN. Fundamentals of chemical kinetics. Visshaia Shkola. 1976.
Urusov VS. Theoreticalcrystal chemistry. Moscow State University. 1987.
Kovba LM. Stoichiometry, defects in crystals and structural homology. Chemistry. 1996.
Butlerov A. On the chemical structure of substances. Scientific notes of Kazan University. (Dep. Physical, mathematical and medical sciences). 1862; 1:1;1.
Klinkova LA, Barkovskii NV, Fedotov VK. Physica C: Superconductivity. 2010; 470:206. https://doi.org/1016/j.physc.2010.09.013
Gay PL, Rao CNR. Z Naturforsch. 1975; 30a:8;1092. https://doi.org/1515/zna-1975-0831
Li Z, Guo W, Zhang NN. APL Matereals. 2020; 8:091112. DOI: 10.1063/5.0018934
Drennan J, Tavares CP, Steele BCH. Mater. Res. Bull. 1982; 17:5;621. https://doi.org/1016/0025-5408(82)90044-7
Savchenko VF, Lyubkina IY. Russian. Inorganic Chemistry. 1986; 2:1483.
Bykova T, Dubrovinsky L, Dubrovinskaia N. Nature Communication. 2016; 10661: https://doi.org/10.1038/neomms10661
Ruddbesden SN, Popper P.Acta Crystall. 1958; 11:1;54. https://doi.org/10.1107/S0365110X58000128
Beznosikov VV. Structural Chem. 1991; 32:3.
Magneli A, Blomberg B, Kihlborg H. Acta chem. scand. 1955; 9:8;1382. https://doi.org/10.3891/acta.chem.scand.09-1382
Andersson S, Collen B, Kuylenstierna U. Acta chem. scand. 1957; 11:10; 1641. https://doi.org/10.3891/acta.chem.scand.11-1641
Andersson S. Acta chem. scand. 1954; 8:9;1599. https://doi.org/10.3891/acta.chem.scand.08-1599
Gado P, Holmberg B, Magneli A.Acta chem. scand. 1965; 19:8;2010. https://doi.org/10.3891/acta.chem.scand.19-2010
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