Comparative optical studies of lanthanide complexes with three types of phosphoro-azo derivatives of beta-diketones

A new class of lanthanide compounds of the formula Na[LnL(4)]. H2O and LnC( 3). 2H(2)O (where L = Wo or Az; Wo = CCl3-C(O)-N-P(O)-(OCH3)(2); Az = C6H5- C(O)-N-P(O)[N(CH2)(2)](2); C = CCl3-C(O)-N-P(O)(NHC6H5)(2)) was obtained fr om mixed solvent solutions with the three types of phosphoro-azo derivative s of the beta-diketones. Spectroscopic properties of these complexes are in vestigated and related to the structure and single crystal spectra of one o f the above mentioned compounds [Amirkhanow et al., J. Appl. Spectr. 62 (19 95) 5; Amirkhanow et al., Acta Phys. Polonica 90 (1996) 455]. The strong in teraction of the ligands with the lanthanides was confirmed both by IR and electronic spectra. The intensities and splitting pattern of the electronic levels were used for the structure determination. IR and Raman spectra in the FIR and MIR regions have been recorded for solid lanthanide(III) (Eu, P r, Nd) complexes with phosphoro-azo-beta-diketones (Wo, Az and C). The norm al coordinate analysis and potential energy distribution were performed for Ln(NPC2O4) molecular system consisting four chelate rings. On that basis, the assignment of the bands observed is proposed and related to the crystal structure of the complexes studied. (C) 1999 Elsevier Science B.V. All rig hts reserved.