Materials Data on CoGeAs2 by Materials Project

Abstract

CoGeAs2 is Chalcopyrite structured and crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Co2+ is bonded to four As3- atoms to form CoAs4 tetrahedra that share corners with four equivalent CoAs4 tetrahedra and corners with eight equivalent GeAs4 tetrahedra. There are one shorter (2.26 Å) and three longer (2.27 Å) Co–As bond lengths. Ge4+ is bonded to four As3- atoms to form GeAs4 tetrahedra that share corners with four equivalent GeAs4 tetrahedra and corners with eight equivalent CoAs4 tetrahedra. All Ge–As bond lengths are 2.53 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded to two equivalent Co2+ and two equivalent Ge4+ atoms to form corner-sharing AsCo2Ge2 tetrahedra. In the second As3- site, As3- is bonded to two equivalent Co2+ and two equivalent Ge4+ atoms to form corner-sharing AsCo2Ge2 tetrahedra.