Exploration of the Structural and Vibrational Properties of the Ternary Molybdate Tl5BiHf(MoO4)6 with Isolated MoO4 Units and Tl+ Conductivity

Victoria Grossman; Sergey V Adichtchev; Victor V Atuchin; Bair G Bazarov; Jibzema G Bazarova; Natalia Kuratieva; Aleksandr S Oreshonkov; Natalia V Pervukhina; Nikolay V Surovtsev

doi:10.1021/acs.inorgchem.0c01762

Exploration of the Structural and Vibrational Properties of the Ternary Molybdate Tl₅BiHf(MoO₄)₆ with Isolated MoO₄ Units and Tl⁺ Conductivity

Inorg Chem. 2020 Sep 8;59(17):12681-12689. doi: 10.1021/acs.inorgchem.0c01762. Epub 2020 Aug 12.

Authors

Victoria Grossman¹, Sergey V Adichtchev², Victor V Atuchin^{3

4

5}, Bair G Bazarov^{1

6}, Jibzema G Bazarova¹, Natalia Kuratieva^{7

8}, Aleksandr S Oreshonkov^{9

10}, Natalia V Pervukhina^{4

7}, Nikolay V Surovtsev²

Affiliations

¹ Laboratory of Oxide Systems, Baikal Institute of Nature Management, SB RAS, Ulan-Ude 670047, Russia.
² Laboratory of Condensed Matter Spectroscopy, Institute of Automation and Electrometry, SB RAS, Novosibirsk 630090, Russia.
³ Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090, Russia.
⁴ Laboratory of Semiconductor and Dielectric Materials, Novosibirsk State University, Novosibirsk 630090, Russia.
⁵ Research and Development Department, Kemerovo State University, Kemerovo 650000, Russia.
⁶ Buryat State University, Ulan-Ude 670000, Russia.
⁷ Laboratory of Crystal Chemistry, Institute of Inorganic Chemistry, SB RAS, Novosibirsk 630090, Russia.
⁸ Laboratory for Research Methods in Composition and Structure of Functional Materials, Novosibirsk State University, Novosibirsk 630090, Russia.
⁹ Laboratory of Molecular Spectroscopy, Kirensky Institute of Physics Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia.
¹⁰ Siberian Federal University, Krasnoyarsk 660079, Russia.

PMID: 32805991
DOI: 10.1021/acs.inorgchem.0c01762

Abstract

The phase relations in the subsolidus region of the Tl₂MoO₄-Bi₂(MoO₄)₃-Hf(MoO₄)₂ system were studied with the "intersecting cuts" method. The formation of the novel ternary molybdate Tl₅BiHf(MoO₄)₆ is found in this ternary system. The compound has a phase transition at T_pt = 731 K (ΔH = -3.15 J/g) and melts at T_m = 871 K (ΔH = -41.71 J/g), as determined by a thermal analysis. Tl₅BiHf(MoO₄)₆ single crystals were obtained by the spontaneous nucleation method. The crystal structure of Tl₅BiHf(MoO₄)₆ was revealed by structure analysis methods. This molybdate crystallizes in the trigonal space group R3̅c with the unit cell parameters a = 10.6801(4) Å, c = 38.5518(14) Å, V = 3808.3(2) Å³, and Z = 6. The vibrational characteristics of Tl₅BiHf(MoO₄)₆ were determined by Raman spectroscopy. The Tl₅BiHf(MoO₄)₆ conductivity was measured at frequencies of 0.1, 1.0, and 10 kHz in the temperature range of 293-773 K; in this temperature range, the conductivity level was 10^-12-10^-7 S/cm.