X-ray Raman spectroscopic study of water in the condensed phases |
| |
Authors: | Tse John S Shaw Dawn M Klug Dennis D Patchkovskii Serguei Vankó György Monaco Giulio Krisch Michael |
| |
Institution: | Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E2, Canada. |
| |
Abstract: | Oxygen K-edge x-ray absorption spectra of high-density amorphous (HDA) ice, low-density amorphous ice Ic, ice Ih, normal and deuterated liquid water were measured with the synchrotron x-ray Raman scattering method under almost identical experimental conditions by in situ heating of an HDA ice sample. The distinct preedge structure previously reported in water was observed in all the spectra. The results show that core-hole excitations are localized and not strongly affected by the local environment. Therefore, the existence of the preedge feature is not a concise indicator of the magnitude of local disorder within the hydrogen bonded network. The intensity of the near-edge absorption shifts into the postedge region when the hydrogen bond network becomes more ordered. This observation is interpreted as an enhancement of Wannier over Frenkel excitations in an ordered crystal. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|