Single-crystal polarized electronic absorption spectra and ligand field parameters for the trichloro(triethylphosphine)platinate(II) ion

Abstract

drogen atoms were placed in calculated positions (C-H = 0.95 Á) and were constrained to ride on their respective carbon atoms.The absolute configuration was assigned by first assuming the R,R configuration. Six final cycles of least-squares refinement converged at R, = 0.0448 and R2 = 0.0493. Anomalous dispersion due to Mo was included in the calculation. The alternate hand of the structure was then refined to convergence from the same starting point, again with six cycles of least-squares refinement, giving a final R, = 0.0466 and R2 = 0.0515. Thus the original assignment of configuration, depicted in Figure 1, was shown to be correct.

Angular Overlap Model Parameters

“…In an early paper, Vanquickenborne and Ceulemans allowed e p for NH 3 in some Pt(II) complexes to vary, ending with a positive value [21]. Later Zink's group assigned positive values of e p (Table 5) to several p-acids, PEt 3 and AsPh 3 , for example, in other Pt(II) complexes, and a correspondingly larger positive value to NMe 3 [66][67][68][69][70]. Conceptually, there are perturbations on the energies of the dp orbitals from beyond the first coordination sphere, which may come from counterions [45], nonbound atoms in a coordinating molecule [35], or electron density from neighboring complexes in the crystal.…”

“…Perhaps the most systematic study on systems other than chromium(III) was carried out by Zink and coworkers on square planar Pt(II) complexes of the type PtX 3 L -, investigated by single crystal polarized spectroscopy [66][67][68][69][70]. AOM parameter values are shown in Table 5.…”

Near-Infrared Electronic Spectroscopy and Emitting-State Properties of K2PdCl4and K2PdBr4

“…Interactions between the metal centers along this axis have been studied in detail for tetracyanoplatinates . Tetrahaloplatinate(II) complexes and their derivatives are well-studied representatives of this coordination geometry with interesting spectroscopic properties. − Some of the isostructural halides of palladium(II) have been known for more than 150 years, but their electronic spectra have received much less attention than those of the platinum analogs. , Emission spectra or luminescence lifetime measurements have been reported only for a limited number of palladium(II) complexes. ,, Luminescence from palladium(II) in the solid state is observed in the near-infrared (near-IR) spectral region, not routinely accessible to standard luminescence spectrometers, and therefore only approximate band maxima 8 or incomplete spectra 20 have been published. The tetragonal crystal structure , and the high D 4h symmetry of the square-planar [PdX 4 ] 2- molecular units make these complexes very attractive from a spectroscopic perspective.…”