CuCl2和CuSO4的核磁共振系数、粘度系数及其与水分子结构的关系

测定了较低浓度范围内CuCl2、CuSO4水溶液的粘度系数(B)、核磁共振(NMR)系数(B')及其对水17O NMR化学位移的影响, 进一步计算了Cu2+、Cl-、SO2-40的粘度系数及核磁共振系数, 并与文献值进行了比较. 利用17O NMR化学位移、粘度系数和核磁共振系数与水团簇结构和水分子缔合的关系, 分析了CuCl2、CuSO4对水结构的影响. 结果表明, CuCl2和CuSO4均具有促进水分子缔合, 使水团簇加大的作用, 且CuSO4对水的缔合作用大于CuCl2, Cl-对水缔合的破坏作用大于SO2-40 . Cu2+作为顺磁离子, 在核磁共振弛豫过程中, 具有明显的缩短水中质子的自旋-晶格弛豫时间, 使谱线变宽的作用.

NMR and Viscosity Coefficients of CuCl2 and CuSO4 and Their Relationship to Water Structure

The viscosity coefficient (B) and nuclear magnetic resonance (NMR) coefficient (B') of CuCl2 and CuSO4 and their effects on the 17ONMR chemical shift (δ) of water were determined at lowconcentrations. Fromthese B and B' values, individual ion's B and B' values were further calculated. These coefficients and the relationship between aqueous solution concentrations and δ(17OH2) represented the effect of ions on water structure and the median water cluster size in aqueous solutions. CuCl2 and CuSO4 were both“structure-makers”. The effect of CuSO4 on water structure and median water cluster size was more powerful than that of CuCl2. Cl- broke more water clusters than SO2-4 . Cu2+ had an obvious effect on shortening the proton spin-lattice relaxation time in water and broadening the line width of the NMR spectrumduring the NMR relaxation process.