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Local Bonding Influence on the Band Edge and Band Gap Formation in Quaternary Chalcopyrites.

ABSTRACT: Quaternary chalcopyrites have shown to exhibit tunable band gaps with changing anion composition. Inspired by these observations, the underlying structural and electronic considerations are investigated using a combination of experimentally obtained structural data, molecular orbital considerations, and density functional theory. Within the solid solution Cu₂ZnGeS_4-_x Se _x , the anion bond alteration parameter changes, showing larger bond lengths for metal-selenium than for metal-sulfur bonds. The changing bonding interaction directly influences the valence and conduction band edges, which result from antibonding Cu-anion and Ge-anion interactions, respectively. The knowledge of the underlying bonding interactions at the band edges can help design properties of these quaternary chalcopyrites for photovoltaic and thermoelectric applications.

SUBMITTER: Miglio A

PROVIDER: S-EPMC5604395 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Local Bonding Influence on the Band Edge and Band Gap Formation in Quaternary Chalcopyrites.

Miglio Anna A Heinrich Christophe P CP Tremel Wolfgang W Hautier Geoffroy G Zeier Wolfgang G WG

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20170522 9

Quaternary chalcopyrites have shown to exhibit tunable band gaps with changing anion composition. Inspired by these observations, the underlying structural and electronic considerations are investigated using a combination of experimentally obtained structural data, molecular orbital considerations, and density functional theory. Within the solid solution Cu2ZnGeS4-x Se x , the anion bond alteration parameter changes, showing larger bond ...[more]

PMID: 28932668

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