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In this paper we present lattice constant values for cubic perovskite solids with the product of ionic charges and average ionic radii rav (Å). The lattice constant of these compounds exhibit a linear relationship when plotted on a log–log scale against the average ionic radii rav (Å), but fall on different straight lines according to the ionic charge product of the compounds. We have applied the proposed relation to ABX3 (A: large cation with different valence, B: transition metal and X: oxides and halides) and found a better agreement with the experimental data as compared to the values evaluated by earlier researchers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

An empirical relationship previously introduced by the authors, relating the ground state properties such as bulk modulus and cohesive energy of rock-salt and zinc blende structured solids to the product of their ionic charges, is shown to be applicable with minor modifications to the more complex class of ternary chalcopyrite semiconductors. The bulk moduli of A I B III C VI 2 and A II B IV C V 2 chalcopyrite semiconductors exhibit a linear relationship when plotted on a log-log scale against the nearest neighbour distance d ( Å), but fall on two straight lines according to the product of the ionic charge of the compounds.On the basis of this result a simple bulk modulus-microhardness relationship is proposed and used to estimate the microhardness of these semiconductors.We have applied the proposed relation to A I B III C VI 2 and A II B IV C V 2 chalcopyrite semiconductors and found a better agreement with experimental data than the values found by earlier researchers. The results for bulk modulus differ from the experimental ones by 0% (CuAlS 2 ), 0% (CuGaSe 2 ), 2% (CuGaS 2 ), 4.8% (CuInSe 2 ), 6% (AgGaS 2 ), 6.2% (CdSiP 2 ) and 0% (CdGeAs 2 ).

The dielectric description of ionicity developed by Phillips and Van Vechten has been successfully employed in a wide range of semi-conductors and insulators. However, the applicability of this Phillips and Van Vechten (PV) dielectric analysis has been limited to only the simple A N B 8-N compounds, which contain only one type of bond. Levine has extended the theory of PV to multi bond and complex crystals. Levine's theory of ionicity has been used to calculate the various bond parameters for the chalcopyrites. In this paper a simple method based on the product of ionic charge and nearest-neighbor distance of solids, is proposed for the calculation of ionic gap (E c ), average energy gap (E g ), crystal ionicity (f i ) and dielectric constant (ε) of zinc blende (A We find the ionic gap (E c ) and average energy gap (E g ) are inversely related to product of ionic charge and nearest-neighbor distance. Our evaluated values are in excellent agreement with the values reported by different researchers.

A new approach utilising the concept of ionic charge theory has been used to explain the inherent properties such as lattice thermal conductivity and bulk modulus of 3,5 and 2,6 semiconductors. The lattice thermal conductivity of these semiconductors exhibit a linear relationship when plotted on a log scale against the nearest neighbour distance but fall on two straight lines according to the product of the ionic charge of the compounds. On the basis of this result a simple relationship of lattice thermal conductivity with bulk modulus is proposed and used to estimate the bulk modulus of these semiconductors. A fairly good agreement has been found between the experimantal and calculated values of these parameters for zinc blende structured solids.Comment: 6 pages, 19 reference

In this paper we have evaluated the ground-state properties (i.e., bulk modulus and cohesive energy) of rocksalt and zinc blende structured solids. We have presented two expressions relating the bulk modulus B (GPa) for the alkali halides, alkaline-earth chalcogenides, transition metal nitrides, rare-earth {divalent (R(2+)X) and trivalent (R(3+)X) } monochalcogenides, group IV, III-V and II-VI semiconductors and the cohesive energy E(coh) (kcal mol(-1)) for the alkali halides and alkaline-earth chalcogenides with the product of ionic charges (Z(1)Z(2)) and nearest-neighbour distance d (Å). The bulk moduli and cohesive energy of rocksalt and zinc blende type structure compounds exhibit a linear relationship when plotted on a log-log scale against the nearest-neighbour distance d (Å), but fall on different straight lines according to the ionic charge product of the compounds. We have applied the modified relation on rocksalt and zinc blende structured solids and found a better agreement with experimental data as compared to the values evaluated by earlier researchers. The results for bulk modulus differ from experimental values by the following amounts: BaO-0%, LiCl-0%, LaS-0%, SmSe-0%, ZnS-0%, CdS-0%, GaP-0%, InP-0%, MgO-0.61%, CaO-0.89%, SmS-1.7%, YbSe-1.6%, UP-1.9%, EuSe-1.9%; and the results for cohesive energy differ from experimental values by the following amounts: LiCl-0.49%, KF-0.51%, RbF-0.54%, SrO-1.2%, NaCl-1.6%, NaF-1.8%, MgSe-1.9%.

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