A theoretical study on the spectral and electrochemical properties of Ferrocene in different solvents

A theoretical-computational study based on Molecular Dynamics simulations and Perturbed Matrix Method (MD-PMM) calculations was carried out for evaluating some properties of solvated Ferrocene including the UV-Vis spectrum and the redox potential. The results, in rather good agreement with the experimental values, display that Ferrocene low-lying excited states are scarcely affected by the change of solvent polarity. On the other hand, the Ferrocene/Ferricinum redox potential show a sharp, although not dramatic, dependency on the nature of the solvent essentially because of the sensitivity of the charged Ferricinium species to the solvent electric field fluctuation. The present study is the first one theoretically addressing, with the use of explicit solvent calculations, the Ferrocene UV spectrum and the Ferricinium/Ferrocene couple redox potential, a quantity proposed by the IUPAC Electrochemical Commission as reference electrode potential for non-aqueous solutions. (c) 2013 Elsevier B.V. All rights reserved

Van der Waals interactions in a monosolvated chiral fluorinated molecule: R2PI vibroelectronic spectra of (R)-1-phenyl-2,2,2-trifluoroethanol clustered with water

One colour mass selected resonant two photon ionization R2PI spectra of supersonically expanded (R)-1-phenyl-2,2,2-trifluoroethanol (FER) and its complex with water are reported. The excitation spectra are analyzed and discussed on the basis of theoretical predictions at the B3LYP/6-31G** level of theory. In the most stable conformer of FER, the OH group establishes an intramolecular hydrogen bond with one of the fluorine atoms of CF3. In the FER/water complex the formation of a structure in which the water molecule acts as proton acceptor from the OH group and proton donor to the fluorine atom of the CF3 group is found. (c) 2007 Elsevier B.V. All rights reserved

Monosolvation of R-1-phenyl-2,2,2-trifluoroethanol with amines: Configurational effects on the excitation, ionization, and fragmentation of diastereomeric complexes

Wavelength and mass selected resonant two-photon ionization spectra of molecular clusters between R-1-phenyl-2,2,2-trifluoroethanol (FER) and methylamine (M) or the enantiomers of 2-aminobutane (A(R) and A(S)) were recorded after supersonic molecular beam expansion and analyzed with the aid of ab initio molecular orbital calculations. The experimental results agree with theoretical calculations pointing to the predominance of the two most stable conformers of monosolvated FER whose CF3 group establishes intense NH center dot center dot center dot F interactions with the selected amines so as to orient them away from the aromatic ring. This reduces the enantio selectivity of FER toward the 2-aminobutane enantiomers as compared to that exhibited by the R-1-phenylethanol (E-R) analogue, where obviously NH center dot center dot center dot F interactions are absent

Monosolvation of R-1-phenyl-2,2,2-trifluoroethanol with amines: configurational effects on the excitation, ionization, and fragmentation of diastereomeric complexes.

Wavelength and mass selected resonant two-photon ionization spectra of mol. clusters between R-1-phenyl-2,2,2-trifluoroethanol (FER) and methylamine (M) or the enantiomers of 2-aminobutane (AR and AS) were recorded after supersonic mol. beam expansion and analyzed with the aid of ab initio MO calcns. The exptl. results agree with theor. calcns. pointing to the predominance of the two most stable conformers of monosolvated FER whose CF3 group establishes intense NHF interactions with the selected amines so as to orient them away from the arom. ring. This reduces the enantioselectivity of FER toward the 2-aminobutane enantiomers as compared to that exhibited by the R-1-phenylethanol (ER) analog, where obviously NHF interactions are absent

Van der Waals interactions in a monosolvated chiral fluorinated molecule: R2PI vibroelectronic spectra of (R)-1-phenyl-2,2,2-trifluoroethanol clustered with water

One colour mass selected resonant two photon ionization R2PI spectra of supersonically expanded (R)-1-phenyl-2,2,2-trifluoroethanol (FER) and its complex with water are reported. The excitation spectra are analyzed and discussed on the basis of theoretical predictions at the B3LYP/6-31G** level of theory. In the most stable conformer of FER, the OH group establishes an intramolecular hydrogen bond with one of the fluorine atoms of CF3. In the FER/water complex the formation of a structure in which the water molecule acts as proton acceptor from the OH group and proton donor to the fluorine atom of the CF3 group is found. (c) 2007 Elsevier B.V. All rights reserved

Host Guest Interactions in Organofluorine Complexes Investgated Through Laser Methodologies.

The successful production of selective supramolecular sensors takes advantage from the development of methods that can predict the structural features of the host necessary to achieve high complexation constants and/or high selectivity toward a definite class of guests. The study of host-guest interactions in the gas phase, without any solvent perturbation, results in a better understanding of the fundamental intrinsic aspects responsible for supramolecular interactions. Recently, we have chosen organofluorine chromophores in order to investigate the aromatic substitution process and the effect of fluorine atom in complex formation. As an example, we will report on the Resonant two Photons Ionization spectroscopy and mass spectrometry of complexes of para-fluoro-sec-butylbenzene with water and sec-butylamine molecule