Dxr smartraman

Resonance Raman spectra were collected in a 180° (780 nm) or 90° (all other lines) geometry. Coherent Innova 70C (5W) Ar⁺ and 300C (1W) Kr⁺ ion lasers were used as the photon sources. The scattered radiation was passed through a longpass filter (Semrock RazorEdge) to remove Rayleigh scattered laser light and then dispersed onto a liquid N₂ cooled 1” Infrared Associates CCD detector using a Princeton Acton spectrograph. The laser power at the sample was kept between 40 and 100 mW in order to prevent possible photo- and thermal degradation of the sample. 780 nm Raman spectra were collected with a Thermo-Scientific DXR SmartRaman, using a low 2 mW laser power due to the observed sensitivity of Cp₂V(bdt) to photodegradation. Solid samples were prepared as finely ground powders and dispersed in a NaCl(s) matrix with Na₂SO₄ added as an internal standard. These samples were subsequently either sealed in a glass capillary tube and spun with a custom-made sample holder or thinly spread on carbon tape and held in a standard brass holder (780 nm). The construction of resonance Raman profiles was accomplished by comparing the integrated intensity of a Raman band at a given excitation wavelength relative to that of the 992.4 cm⁻¹ band of Na₂SO₄ or solvent bands. All data were scan-averaged, and any individual data set with vibrational bands compromised by cosmic events was discarded.