A new family of anti-perovskite oxyhydrides with tetrahedral GaO4 polyanions

Nur Ika Puji Ayu; Fumitaka Takeiri; Takafumi Ogawa; Akihide Kuwabara; Masato Hagihala; Takashi Saito; Takashi Kamiyama; Genki Kobayashi

doi:10.1039/d3dt01555f

A new family of anti-perovskite oxyhydrides with tetrahedral GaO₄ polyanions

Dalton Trans. 2023 Oct 31;52(42):15420-15425. doi: 10.1039/d3dt01555f.

Authors

Nur Ika Puji Ayu^{1

2}, Fumitaka Takeiri^{2

3

4

5}, Takafumi Ogawa⁶, Akihide Kuwabara⁶, Masato Hagihala^{1

2}, Takashi Saito^{1

2}, Takashi Kamiyama^{1

2

7

8}, Genki Kobayashi^{2

3

5}

Affiliations

¹ Neutron Science Laboratory (KENS), Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 203-1 Shirakata, Tokai, Ibaraki 319-1106, Japan.
² SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa 240-0193, Japan.
³ Department of Materials Molecular Science, Institute for Molecular Science, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan.
⁴ PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan.
⁵ Solid State Chemistry Laboratory, Cluster for Pioneering Research (CPR), RIKEN, Wako 351-0198, Japan. fumitaka.takeiri@riken.jp.
⁶ Nanostructures Research Laboratory, Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya 456-8587, Japan.
⁷ Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
⁸ China Spallation Neutron Source Science Center, Dongguan, 523803, China.

PMID: 37366341
DOI: 10.1039/d3dt01555f

Abstract

New solid compounds A_3-xGaO₄H_1-y (A = Sr, Ba; x ∼0.15, y ∼0.3), which are the first oxyhydrides containing gallium ions, have been synthesized by high-pressure synthesis. Powder X-ray and neutron diffraction experiments revealed that the series adopts an anti-perovskite structure consisting of hydride-anion-centered HA₆ octahedra with tetrahedral GaO₄ polyanions, wherein the A- and H-sites show partial defect. Formation energy calculations from the raw materials support that stoichiometric Ba₃GaO₄H is thermodynamically stable with a wide band gap. Annealing the A = Ba powder under flowing Ar and O₂ gas suggests topochemical H^- desorption and O^2-/H^- exchange reactions, respectively.