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Threefold coordinated germanium in a GeO₂ melt.

ABSTRACT: The local structure around germanium is a fundamental issue in material science and geochemistry. In the prevailing viewpoint, germanium in GeO₂ melt is coordinated by at least four oxygen atoms. However, the viewpoint has been debated for decades due to several unexplained bands present in the GeO₂ melt Raman spectra. Using in situ Raman spectroscopy and density functional theory (DFT) computation, we have found a [GeOØ₂]_n (Ø = bridging oxygen) chain structure in a GeO₂ melt. In this structure, the germanium atom is coordinated by three oxygen atoms and interacts weakly with two neighbouring non-bridging oxygen atoms. The bonding nature of the chain has been analyzed on the basis of the computational electronic structure. The results may settle down the longstanding debate on the GeO₂ melt structure and modify our view on germanate chemistry.

SUBMITTER: Wan S

PROVIDER: S-EPMC10622558 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Threefold coordinated germanium in a GeO2 melt.

Wan Songming S Zhang Shujie S Li Bin B Zhang Xue X Gong Xiaoye X You Jinglin J

Nature communications 20231102 1

The local structure around germanium is a fundamental issue in material science and geochemistry. In the prevailing viewpoint, germanium in GeO2 melt is coordinated by at least four oxygen atoms. However, the viewpoint has been debated for decades due to several unexplained bands present in the GeO2 melt Raman spectra. Using in situ Raman spectroscopy and density functional theory (DFT) computation, we have found a [GeOØ2]n (Ø = bridging oxygen) chain ...[more]

PMID: 37919318

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