Vibrational dynamics of iron pentacarbonyl in cryogenic matrices.

Iron pentacarbonyl is a textbook example of fluxionality. We trap the molecule in cryogenic matrices to study the vibrational dynamics of CO stretching modes involved in the fluxional rearrangement. The infrared spectrum in Ar and N is composed of about ten narrow bands in the spectral range of interest, indicating the population of various lattice sites and a lowering of the molecular symmetry in the trapping sites.

Vibrational spectroscopy and dynamics of W(CO) in solid methane as a probe of lattice properties.

Methane solids present more than one accessible crystalline phase at low temperature at zero pressure. We trap W(CO) in CH and CD matrices between 8 and 35 K to probe the interaction between an impurity and its surrounding molecular solid under various physical conditions. Linear and nonlinear vibrational spectroscopies of W(CO) highlight different kinds of interaction and reveal new and remarkable signatures of the phase transition of methane.

Stimulated emission in cryogenic samples doped with free-base tetraazaporphine.

Thin cryogenic samples of inert gas solids doped with free-base tetraazaporphine (H2TAP) were irradiated with a tunable pulsed laser. Under resonant electronic excitation of the guest, specific vibronic transitions of the fluorescence spectra were found to be strongly enhanced with only a moderate increase of the laser power. This enhancement is due to stimulated emission (SE).

Free base tetraazaporphine isolated in inert gas hosts: matrix influence on its spectroscopic and photochemical properties.

The absorption, fluorescence, and excitation spectra of free base tetraazaporphine (H2TAP) trapped in Ne, N2, and Ar matrices have been recorded at cryogenic temperatures. Normal Raman spectra of H2TAP were recorded in KBr discs and predicted with density functional theory (DFT) using large basis sets calculations. The vibrational frequencies observed in the Raman Spectrum exhibit reasonable agreement with those deduced from the emission spectra, as well as with frequencies predicted from large basis set DFT computations.

[Botulinum A toxin and detrusor sphincter dyssynergia: retrospective study of 47 patients].

Introduction: To assess the efficacy of injections of botulinum toxin type A (BT-A) in the urethral sphincter for treating detrusor sphincter dyssynergia (DSD).

Patients And Methods: Retrospective observational study of patients with confirmed urodynamic DSD (neurological and non-neurological etiologies) treated at our center from 2002 to 2010. All patients received 300 IU of DYSPORT® injected transperineally under electromyographic control.