Effect of ligand nature and geometry of its surrounding on electron absorption spectra of NpO22+ and PuO22+ compounds

Electron absorption spectra of actinide compounds with the symmetry of the nearest surrounding of actinyl-ions as follows: Dsub(2h)-AnO2(NO3)2xnH2O, AnO2(CH3COO)2x2H2O; Dsub(3h)-MAnO2(NO3)3 (M-K, Rb, Cs), NaAnO2(CH3COO)3, (NH4)4AnO2(CO3)3; Dsub(4h)-Cs2AnO2Cl4, where An-U, Np, Pb, are measured at room temperature. It is established that position, intensity and form of absorption bands in neptunyl compound spectra are sensible equally to geometry of coordination sphere and to ligand nature. The character of the change of plutonyl compound spectra is the same as of neptunyl ones: it is determined both by surrounding geometry and chemical nature of ligands. It is shown that in the near infrared region ligand effect on plutonyl compound spectra with the symmetry of anion complex Dsub(3h) is weaker than in the visible region