Browsing by Author "Abbate, S."
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ANALYSIS OF THE TRANSITION FROM NORMAL MODES TO LOCAL MODES
Abbate, S.; Longhi, G.; Zagano, C.; Botto, G.; Ghisletti, D.; Lespade, L. ( 1991 )By numerical integration of the classical equations of motion for a system of two coupled anharmonic oscillators, one can define the vibrational motions as follows: normal modes, for which energy is exchanged between the ... 
ANALYTICAL DESCRIPTION OF FREQUENCIES, DIPOLE STRENGTHS AND ROTATIONAL STRENGTHS FOR FUNDAMENTAL AND OVERTONE CHSTRETCHING TRANSITIONS
Longhi, G.; Gangemi, R.; Abbate, S. ( 2002 )The normal mode to local mode transition has been described in the past by basic arguments centered on symmetry and on perturbativetype numerical quantum mechanical $calculations^{ab}$. In this work we investigate the ... 
ANALYTICAL EXPRESSIONS OF FREQUENCIES, DIPOLE STRENGTHS AND ROTATIONAL STRENGTHS FOR OVERTONE TRANSITIONS IN A DISSYMMETRIC HCCH FRAGMENT
Gangemi, R.; Longhi, G.; Lebon, F.; Abbate, S. ( 2003 )In a recent $paper^{a}$ we derived useful analytical expressions for frequencies, dipole strengths and rotational strengths for CHstretching transitions $\Delta v = 1, 2, 3$ in a two degrees of freedom model of an HCCH ... 
CALCULATIONS OF VIBRATIONAL CIRCULAR DICHROISM SPECTRA FROM CLASSICAL TRAJECTORIES
Abbate, S.; Longhi, G.; Kwon, Kyonghai ( 1998 )By use of a general formula for Circular Dichroism (CD) spectra in terms of crosscorrelation functions of electric and magnetic dipole $moments^{(1)}$, we have calculated the semiclassical vibrational CD spectra associated ... 
CHARACTERIZATION OF NONADIABATIC RESONANT STATES FOR METHANOL CH AND OH STRETCHING MODES BY THE USE OF CLASSICAL MECHANICS
Chietera, L.; Montagnoli, Enrico; Longhi, G.; Abbate, S. ( 1999 )Methanol CH and OHstretching overtones have been the subject of numerous studies (a) and in 1998 a full session of this Conference was dedicated to various aspects of the spectroscopy of this molecules (b). We focused ... 
CHARGE FLOW MODEL ANALYSIS OF A SERIES OF CYCLIC KETONES
Laux, Leo J.; Abbate, S. ( 1981 )We have measured the VCD spectra of a number of cyclic ketone derivatives. These data, together with previously reported VCD data for cyclohexanone derivatives, are analyzed on the basis of the charge flow $model.^{1}$ ... 
CLASSICAL AND SEMICLASSICAL DYNAMICS OF A CHBOND BELONGING TO AN ALMOST FREELY ROTATING METHYL GROUP
Abbate, S.; Longhi, G.; Meazza, S.; Abate, C.; Biancardi, L. ( 1995 )In the course of the years $Cavagnat et al^{(1)}$ have recorded the intrared and Raman spectra of molecules containing $CHD_{2}$groups in the CHstretching region and, most recently, they have recorded spectra also in the ... 
CLASSICAL DYNAMICS OF LOCAL CHSTRETCHINGS OF AN ALMOST FREELY ROTATING METHYL GROUP
Abbate, S.; Montagnoli, Enrico; Longhi, G. ( 1998 )Cavagnat and Lespade have extensively examined the CHstretching fundamental and overtone spectra of molecules containing an almost freely rotating $CHD_{2}$group: Nitromethane. Toluene, etc. They were able to interprete ... 
CLASSICAL DYNAMICS OF TWO COUPLED TORSIONAL MODES
Conti, Giuseppina; Abbate, S. ( 1995 )We have investigated numerically the classical dynamics of two HCOC torsions, sharing the COC fragment. We have described completely their kinetic interaction through the formulae by Decius (1). We have assumed that their ... 
COMPARISON OF ABSORPTION SPECTRA IN THE RANGE 20001700 nm WITH POWER SPECTRA OF CLASSICAL TRAJECTORIES IN MOLECULES CONTAINING $CH_{2}$ GROUPS
Longhi, G.; Abbate, S. ( 1994 )It is generally thought that the vibrational spectra relative to the transition $\Delta w=2$ for $XH_{2}$ systems are intermediate between those typical of normal modes, which are observed for $\Delta v=1$, and those typical ... 
A COMPARISON OF THE CHARGE FLOW AND LOCALIZED MOLECULAR ORBITAL MODELS
Pultz, Vaughan M.; Laux, Leo J.; Abbate, S.; Overend, John; Moscowitz, Albert ( 1982 )Recently, the localized molecular orbital $model^{1}$ and the charge flow $model^{2}$ have been put forth in attempts to provide a more sophisticated interpretation of vibrational circular dichroism data than that provided ... 
DOES THE CIRCULAR DICHROISM OF CHSTRETCHING OVERTONES HELP ONE TO DISTINGUISH BETWEEN NORMAL MODES AND LOCAL MODES?
Abbate, S.; Longhi, G.; Lebon, F.; Gangemi, R. ( 2003 )Several years ago we presented a number of Vibrational Circular Dichroism (VCD) spectra of natural compounds in the CHstretching 2nd and 3rd overtone $regions^{a}$. In that paper we pointed out that normal modes and local ... 
HIGH VIBRATIONAL STATES OF 1,2,3,4,4,5,5d7 and 3,3,4,4d4 CYCLOPENTENES.
RodinBercion, S.; Cavagnat, D.; Lespade, L.; Abbate, S. ( 1993 )The ringpuckering motion of cyclopentene is studied through the CH bond stretching overtones $(\Delta v=1$ to 6) of the monohydrogenated and dihydrogenated $molecules^{1}$. At high energies, the potential of the large ... 
INTERPRETATION OF NEARINFRARED CIRCULAR DICHROISM SPECTRA THROUGH THE FOURIER CROSS SPECTRA OF CLASSICAL TRAJECTORIES
Abbate, S.; Longhi, G.; Kwon, Kyonghai; Moscowitz, Albert ( 1995 )Following the general scheme employed by $Gordon^{(1)}$, we have shown that the Circular Dichroism spectrum is proportional to the imaginary part of the Fourier transform of the crosscorrelation function of the electric ... 
NEAR INFRARED CIRCULAR DICHROISM SPECTRA OF (3R)METHYL CYCLOHEXANONE AND (3R)METHYL CYCLOPENTANONE
Abbate, S.; Longhi, G.; Lespade, L.; Cavagnat, D.; Bertucci, C.; Salvadori, P. ( 1991 )The circular dichroism spectra of (3R)Methyl cyclohexanone and (3R)Methyl cyclopentanone have been recorded in the range 2000800 nm, covering the vibrational overtone for $\Delta$v=2, 3, 4. By comparing with the CD data ... 
OVERTONE CIRCULAR DICHROISM SPECTRA OF A CHIRAL HCCH MOLECULAR FRAGMENT INTERPRETED BY CROSS CORRELATIONS OF CLASSICAL TRAJECTORIES
Abbate, S.; Longhi, G.; Kwon, Kyonghai ( 1997 )A class of several chiral cyclic molecules containing a $CH_{2}CH_{2}C^{*} H$ fragment exhibit similar infrared circular dichroism spectra, the gross features of which have been elucidated some time ago(1). The corresponding ... 
THE ROLE OF CHARGE FLOWS IN VIBRATIOBNAL ROTATIONAL STRENCTHS
Abbate, S.; Laux, Leo J.; Overend, John; Moscowitz, Albert ( 1980 )A model for estimating the contribution of electron charge flows in the generation of vibrational rotational strengths will be presented. The model preserves the origin independence of calculated values of rotational ... 
SIGNIFICANCE OF THE PHENYL GROUP FOR THE DIPOLE STRENGTHS AND ROTATIONAL STRENGTHS IN DEUTERATED PHENYLETHANES
Havel, Henry A.; Abbate, S.; Laux, Leo J.; Pultz, Vaughan M.; Overend, John; Moscowitz, Albert ( 1981 )Measurements of the circular dichroism spectra in the 35 $\mu$m region have now been completed for the entire series of molecules $S(+)PhCHCX (X = CH_{3}, CH_{2}D, CD_{2}H, CD_{3}).^{1}$ Chargeflow $model^{2}$ ... 
STUDY OF CHSTRETCHING MODES IN A CHIRAL HCCH FRAGMENT WITH LARGE AMPLITUDE TORSIONAL MOTIONS
Abbate, S.; Longhi, G.; Santina, C. ( 1999 )Vibrational Circular Dichroism (VCD) spectra in the CHstretching overtone region (up to $\Delta v=6$) have been observed for cyclic molecules with relatively low barrier torsional twisting or puckering modes (a). This has ... 
TRANSFERABILITY OF ELECTROOPTICAL PARAMETERS FOR INFRARED INTENSITIES OF NORMAL PARAFFINS
Abbate, S.; Gussoni, M.; Zerbi, Giusepp ( 1976 )The intensity of infrared absorption for the ith normal mode $\theta_{1}$ depends on $\left( \frac{\vec{\partial M}}{\partial Q_{i}} \right)^{\circ}$ where $\vec{M}$ is the total dipole moment of the molecule. $\left( ...