Experimental and ab initio study of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F stability in the pressure range of 0–10 GPa  

作　　者：Nursultan E.Sagatov Tatyana B.Bekker Yulia G.Vinogradova Alexey V.Davydov Ivan V.Podborodnikov Konstantin D.Litasov 

机构地区：[1]Sobolev Institute of Geology and Mineralogy,Siberian Branch of Russian Academy of Sciences,Novosibirsk 630090,Russia [2]Department of Geology and Geophysics,Novosibirsk State University,Novosibirsk 630090,Russia [3]Research and Development Department,Novosibirsk State University of Architecture,Design and Arts(NSUADA)Novosibirsk 630099,Russia [4]Vereshchagin Institute for High Pressure Physics,Russian Academy of Sciences,Troitsk 108840,Russia [5]Fersman Mineralogical Museum,Russian Academy of Sciences,Moscow 119071,Russia

出　　处：《International Journal of Minerals,Metallurgy and Materials》2023年第9期1846-1854,共9页矿物冶金与材料学报（英文版）

基　　金：financially supported by the Russian Science Foundation (No.21-19-00097)。

摘　　要：Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that Ba_(2)Na_(3)(B_(3)O_(6))_(2)F has an indirect band gap of 6.289 eV. A numerical study revealed the decomposition of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F into the BaB_(2)O_(4),Na BO_(2), and NaF phases above 3.4 GPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 GPa and temperature of 1173 K confirmed the stability of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F at 3 GPa and its decomposition into BaB_(2)O_(4), NaBO_(2), and NaF at 6 GPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the Ba_(2)Na_(3)(B_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 GPa suggest the origin of a new high-pressure modification of barium metaborate BaB_(2)O_(4).

关 键 词：density functional theory phase stability BORATE high pressure Raman spectroscopy 

分 类 号：TQ132.35[化学工程—无机化工]