Accession Number : ADA231227


Title :   Ab Initio Study of the Electric Dipole Transition Moment for the Electronic X to C Transition in Acetylene: Theoretical Predictions of the Absorption and Magnetic Circular Dichroism Intensities


Descriptive Note : Final rept. Sep 1988-May 1990


Corporate Author : ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD


Personal Author(s) : Jensen, James O ; Adams, George F ; Chabalowski, Cary F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a231227.pdf


Report Date : Dec 1990


Pagination or Media Count : 37


Abstract : The electric dipole transition moment has been cancelled a priori for the electronic transition as a function of R(C-C), using ab initio quantum chemical techniques including state averaged, complete active space MCSCF and multireference CI. The transition moment is then averaged over the vibrational wavefunctions for the C-C stretch, and theoretical predictions are made for the absorption oscillator strength and the magnetic circular dichroism (MCD) intensities, for the lowest four vibrational bands originating from v=0 in X. This study predicts an oscillator strength for absorption of f=0.157 (summed over v'=0-3), to be compared to an early experimental value of 0.062 + or - . 0092. And for the MCD 0-0 band, the calculations predict 0.0179 while the experimental value is reported to be 0.0125 + or - .001 (cgs units).


Descriptors :   *BANDS(STRIPS) , ABSORPTION , ACETYLENE , CHEMICAL ENGINEERING , CIRCULAR , DICHROISM , DIPOLES , ELECTRIC MOMENTS , ELECTRON TRANSITIONS , INTENSITY , MAGNETIC FIELDS , MOMENTS , OSCILLATORS , PREDICTIONS , QUANTUM CHEMISTRY , STRENGTH(GENERAL) , THEORY , TRANSITIONS , VIBRATION , WAVE FUNCTIONS


Subject Categories : Organic Chemistry


Distribution Statement : APPROVED FOR PUBLIC RELEASE