Metal coordination study at Ag and Cd sites in crown thioether complexes through DFT calculations and hyperfine parameters

RAFAEL R. DO NASCIMENTO; FILIPE C. D. A. LIMA; MARCOS B. GONÇALVES; L. A. ERRICO; M. RENTERIA; H. M. PETRILLI

JOURNAL OF MOLECULAR MODELING - (Print)

SPRINGER

Lugar: Berlin; Año: 2001

1610-2940

Structural and electronic properties of [C12H24S6X], [C13H26S6OX], and [C14H28S6OX] (X: Ag+, Cd2+) crown thioether complexes are investigated within the framework of the Density Functional Theory (DFT) using the Projector Augmented Wave (PAW) method. The theoretical results are compared with Time-Differential Perturbed - Angular Correlations (TDPAC) experiments reported in the literature, using the 111Ag→111Cd probe. In the case of X=Ag+ a refinement of the structure is performed and the predicted equilibrium structures are compared with available X-ray diffraction experimental data. Structural distortions induced by replacing Ag+ by Cd2+ are investigated as well as the electric-field gradient (EFG) tensor at the Cd2+ sites. Our results suggest that the EFG at Cd2+ sites corresponds to the Ag+ coordination sphere structure, i.e., before the structural relaxations of the X=Cd2+ molecule are completed. This point is discussed in terms of the characteristics of the TDPAC 111Ag→111Cd probe and the time window of the measurement, presenting an interesting tool to probe molecular relaxations.