Spectroscopy of mass-selected rhodium dimers in argon matrices

Abstract

The absorption ͑scattering depletion͒ spectrum and Raman spectra for Rh 2 in an argon matrix prepared by the mass selected ion deposition technique have been obtained. The absorption spectrum in the visible region shows a single broad transition centered near 495 nm Resonance Raman spectra obtained by exciting with eight visible lines ͑457.9-514.5 nm͒ of an argon ion laser give a single, sharp progression with up to four Stokes transitions. These data give e ϭ283.9 ͑18͒ cm Ϫ1 with e x e ϭ1.83 ͑33͒ cm Ϫ1 , leading to an experimental dissociation energy of 1.4Ϯ0.3 eV. The Raman results are discussed in the context of previous theoretical predictions for the dimer.

Investigation of the use of density functionals in second‐ and third‐row transition metal dimer calculations

“…By taking 400,000 electronic configurations into account, CASSCF followed by MRCI (CASSCF/MRCI) method 41 42 and ω e = 283.9±1.8 cm −1 . 43 Calculated MP2 results are thus inaccurate. The BOP functional slightly overestimates the dissociation energy, while the B3LYP functional considerably underestimates it.…”

Probing the structures of gas-phase rhodium cluster cations by far-infrared spectroscopy

“…Spectroscopic investigations of rhodium clusters, which can provide experimental details of their structure, are limited. The stretching frequency 29 and bond dissociation energy 30 of the dimer have been measured, while electron spin resonance spectroscopy determined the trimer to have D 3h symmetry. 31 We have recently reported a combined far-infrared multiple photon dissociation (FIR-MPD) spectroscopy and DFT study of Rh + 8 , from which we determined the structure to be a bicapped octahedron (bc-oh).…”

Communications: The structure of Rh8+ in the gas phase

“…Test calculations at the PBE1/ lanl2dz level for the neutral dimer give a frequency of 304.5 cm −1 for the 5 ⌺ u electronic state, close to the experimental value of 283.9͑18͒ cm −1 that has been obtained from matrix isolation resonance Raman spectroscopy. 37 Given the difficulties experienced by current DFT methods in TM dimer systems with significant multiconfigurational character 38 -a group which includes Rh 2 39,40 -one has to be careful with this comparison. However, in similar cases such comparisons have been used to obtain an optimal scaling factor 23 and we now take it as an indication that the factor to be used here will be close to unity.…”