VO(Ⅱ)-邻菲啰啉络合物的ESR波谱研究

该文考察了VOSO₄与1,10-邻菲啰啉(Phen)和3,4,7,8-四甲基-1,10-邻菲啰啉(TMP)在不同酸度(pH=1-14)的乙二醇/水(1:1)溶液中,在-100℃下的ESR波谱.发现在pH<1.0和pH>11范围内,二种配体均不能与VO(Ⅱ)生成络合物,当pH<1.0时,A=118×10^-4T归属于VO(H₂O)₅]²⁺;当pH>11时,A=90×10^-4T归属于VO(OCH₂CH₂O)₂]^2-.在1.4 < pH < 6之间,VO(Ⅱ)与phen生成三种不同络合物,在1.0 < pH < 7之间,VO(Ⅱ)则可与TMP生成四种络合物.本文推测了它们的可能结构.利用测得的波谱参数,计算了键参数和电子能级.利用电子光谱数据计算了晶体场参数.

ESR STUDIES ON THE OXOVANADIUM PHENANTHROLINE COMPLEXES

The ESR spectra of oxovanadium 1,10-phenanthroline and 3,4,7,8-tetramethyl-1,10-phcnanthroline complexes in glycol water(1:1) solution at various acidity (pH=1-14) have been observed at -100℃. It was found that within the range of 1.4 < pH < 6 phenanthroline can coordinate with oxovanadium to form three complexes and that within the range of 1.0 < pH < 7 3,4,7,8 -tetramethyl-1,10-phenanthroline can coordinate with oxovanadium to form four complexes. Their possible structures were suggested in this paper. When pH-4T is attributed to the complexVO(H₂O) ₅]²⁺; when pH>11 A=90×10^-4T is attributed to the bidentate chelate of glycolVO (OCH₂CH₂O)₂]^2- at a ratio of 1:2 of VO(Ⅱ):glycol. The bonding parameters and electronic energy levels were calculated using the spectral parameters measured. It was found that the values of bonding parameters decrease with the increasing of pH values of the solution. The data of electronic energy levels agree fairly well with the experimental, results.