Hypersensitive spectra and coordination structures of trivalent neodynium ion

Hypersensitive absorption spectra were used to study the coordination structure of Nd
³⁺
complexes in solutions. The method of theoretical spectroscopic calculation is briefly described. Crystalline complexes with known symmetries: NdCl
6
3Ph
3
PH, Nd [(C
2
H
5
O)
2
PO
2
]
3
and Nd(TTA)
4
HQ having O
h
, O
h
and D
4d
symmetry, respectively, were prepared and the f-f transition spectra of Nd
³⁺
were measured in acetonitrile solution. Spectra calculated for these complexes fit the experimental data quite well. Spectroscopic calculation reveals that the band shape and transition strength of hypersensitive spectra are mainly affected by changes of the donor atom and coordination symmetry. The coordination structure of the TRPO extraction complex of Nd
³⁺
was studied using this method. A D
3h
symmetric coordination structure is assigned to Nd(NO
3
)
3
3TRPO complex in dodecane.