用θ-2θ型粉末衍射仪精确测定溶液结构的新尝试

A New Attempt to Determine Solution Structure with θ - 2θ Type Powder Diffractometer

发展了用θ-2θ型衍射仪测定电解质水溶液结构的新方法.设计了具有恒温功能的超厚液体样品池并建议池窗口强度的校正规程.获得了令人非常满意的实验结果.θ-2θ型粉末衍射仪测定的径向分布函数与θ-θ型衍射仪的自由表面散射比较,表明径向分布函数分辨率有所提高.

A new method for determining the structure of aqueous electrolyte solution using θ-2θ typepowder diffractometer has been developed. The thermostatic super - thick liquid sample cells have been designed and the correction procedures for the diffraction intensity of window on the cell proposed. A very satisfactory experimental result of molten salt of hexaquamanganese nitrate has been obtained. Acomparison between the radial distribution function curve with the θ-2θ type diffractometer and that withthe θ-θ type diffractometer by the free surface scattering shows that the resolution has improved to someextent. The hydrogen bonding distance of 0.28nm from the cis-O-O interaction of 0.31 run in the first coordination shell in the octahedral complex ion of [ Mn ( H2O)5 ( ONO2) ]+ and the Mn-N distance of 0.309nm in the contact ion pair have been clearly distinguished. Then the Mn-O( II ) peak at 0.42nm from the trans-O-O peack at 0.44nm has been separated out. With the improvement of the resolution, some ripples occured in the high r zone. This is to be overcome.