Negative Knight Shift in Ba-Ti Oxyhydride: An Indication of the Multiple Hydrogen Occupation
Negative Knight Shift in Ba-Ti Oxyhydride: An Indication of the Multiple Hydrogen Occupation
复制标题
Ba-Ti 氢氧化物中的负骑士位移:多重氢占据的迹象
DOI:
10.1021/acs.chemmater.9b01434
复制
发表时间:
2019
影响因子:
8.6
通讯作者:
Takamura Hitoshi
中科院分区:
文献类型:
--
作者:
Misaki Tai;Oikawa Itaru;Takamura Hitoshi
Multiple hydrogen occupation in Ba-Ti oxyhydride is demonstrated by a negative Knight shift in the1H magic-angle spinning (MAS) NMR spectra combined with hydrogen concentration and X-ray photoelectron spectroscopic analysis. A negative Knight shift, an indicator of the interaction between conduction band electrons and a probe nucleus, is observed in the1H MAS NMR signal of Ba-Ti oxyhydrides at room temperature for the first time. This Knight shift indicates multiple hydrogen occupation. This was confirmed by the X-ray photoelectron spectra of Ba-Ti oxyhydrides and the hydrogen concentrations. The presence of hydrogen species with different bonding characteristics indicates a flexible hydrogen configuration in Ba-Ti oxyhydrides, from an ionic-state hydride ion with single occupation to partially anionic state hydrogen atoms with multiple occupation. It also indicates the potential to modify the electronic structure and physical properties of Ba-Ti oxyhydrides by manipulating their hydrogen configuration.