A thorough investigation of the crystal structure of willemite‐type Zn2GeO4. Issue 23 (26th October 2021)

• Record Type: Journal Article
• Authors: Breternitz, Joachim; Fritsch, Daniel; Franz, Alexandra; Schorr, Susan
• Is Part Of: Zeitschrift für anorganische und allgemeine Chemie. Volume 647:Issue 23/24(2021)
• Page Start: 2195
• Page End: 2200
• Publication Date: 2021-10-26
• Subjects: neutron diffraction -- ab initio calculation -- ternary oxide -- crystal structure; Chemistry, Inorganic -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1002/zaac.202100231
• Languages: English
• ISSNs: 0044-2313

Abstract

Abstract: The thermodynamically stable phase of Zn2 GeO4 contains tetrahedrally coordinated cations only and crystallizes isostructurally to Zn2 SiO4 (willemite, space group R 3 ‾, no. 148). While this material is considered for a plethora of energy‐related applications, such as transparent conducting oxide, battery material and photocatalyst, cation ordering in the crystal structure has not been investigated thoroughly. We have therefore re‐determined the crystal structure of Zn2 GeO4 using a combination of X‐ray and neutron powder diffraction. The additional neutron diffraction study helps to distinguish between the isoelectronic Zn 2+ and Ge 4+ cations and yields valuable information about a partial or complete cation permutation in this material. The experimental study is supported by first‐principles calculations on the structural properties of Zn2 GeO4 utilizing a standard generalized gradient approximation, and the more accurate hybrid functional HSE06. In order to better understand cation permutations, additional calculations including defective Zn2 GeO4 have been performed based on a supercell approach. Our results show that, with the preparation conditions applied, cation permutation is unlikely to occur in our samples. Abstract :