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cadmium which has lower bandgap due to low bandgaps of the constituent
compounds. On the other hand, stable compounds along the block diagonal
2 (top left to bottom right) are low bandgap mixtures with the bandgap 1.5
eV. Thus, the dichotomy in the bandgaps allows us to look in a definite region
of the materials space for the required range of bandgaps suitable for the
application in hand.
6.3 Conclusion
In the current work we have carried out a systematic analysis of the compounds
in different crystal structures spanning a wide range of volumes and
having the AB stoichiometry. The correlation between the crystal structure
and the chemical scale factor gives a rationale to understand the effect of
electronegativity on the crystal structure of the compounds. In addition to
the binary compounds, detailed analysis of their alloys gives a rationale for
the bandgap engineering via solid solutions of the semiconductors. The analysis
carried out in the current work for the binary semiconductors can also be
generalized to the systems containing more than two elements thus providing
an elegant route to tailor the bandgap as required by the application in hand
like photo-electrochemical water splitting, solar cells.