Hybridization Gap in the Semiconducting Compound SrIr4In2Ge4

Nicholas P Calta; Jino Im; Lei Fang; Thomas C Chasapis; Daniel E Bugaris; Duck Young Chung; Wai-Kwong Kwok; Mercouri G Kanatzidis

doi:10.1021/acs.inorgchem.6b02617

Hybridization Gap in the Semiconducting Compound SrIr₄In₂Ge₄

Inorg Chem. 2016 Dec 5;55(23):12477-12481. doi: 10.1021/acs.inorgchem.6b02617. Epub 2016 Nov 18.

Authors

Nicholas P Calta^{1

2}, Jino Im³, Lei Fang^{1

4}, Thomas C Chasapis¹, Daniel E Bugaris⁴, Duck Young Chung⁴, Wai-Kwong Kwok⁴, Mercouri G Kanatzidis^{1

4}

Affiliations

¹ Department of Chemistry, Northwestern University , Evanston, Illinois, United States.
² Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory , Livermore, California, United States.
³ Center for Molecular Modeling and Simulation, Chemical Infrastructure Division, Korea Research Institute of Chemical Technology , Daejeon, Ulsan, South Korea.
⁴ Materials Science Division, Argonne National Laboratory , Lemont, Illinois, United States.

PMID: 27934417
DOI: 10.1021/acs.inorgchem.6b02617

Abstract

Large single crystals of SrIr₄In₂Ge₄ were synthesized using the In flux method. This compound is a hybridization gap semiconductor with an experimental optical band gap of E_g = 0.25(3) eV. It crystallizes in the tetragonal EuIr₄In₂Ge₄ structure type with space group I4̅2m and unit cell parameters a = 6.9004(5) Å and c = 8.7120(9) Å. The electronic structure is very similar to both EuIr₄In₂Ge₄ and the parent structure Ca₃Ir₄Ge₄, suggesting that these compounds comprise a new family of hybridization gap materials that exhibit indirect gap, semiconducting behavior at a valence electron count of 60 per formula unit, similar to the Heusler alloys.