The potential energy surfaces of acetyl cyanide and its functional isomer acetyl isocyanide in their electronic ground state have been investigated using ab initio molecular orbital MP2(FU)/6-311G** and QCISD(T)/6311G** calculations. The molecular eliminations of CH3COX (X ) CN,NC) to CH3X + CO, HX + CH2CO, and CH2 + HCOX, the unimolecular rearrangements to CH3C-OX and CH3O-CX carbenes, 1,3-hyd...

The relative reactivity of a series of nucleophiles that includes ethylene, sulfides, sulfoxides, amines, and phosphines toward dioxirane, dimethyldioxirane, carbonyloxide and dimethylcarbonyloxide has been U U Ž . U examined at the MP4r6-31G rrMP2r6-31G , QCISD T r6-31G rrMP2r631G , and B3-LYPr6-31G levels of theory. The barriers for the oxidations with Ž . dimethyldioxirane are higher up to 2...

The reaction mechanism of the gas-phase HO-initiated oxidation of furan has been investigated by means of high level theoretical methods. The reaction is a complex process that begins with the formation of a pre-reactive hydrogen bonded complex, previous to the addition of the HO radical to furan, forming the 2 and 3-HO-adducts. In the prereactive complex, the hydrogen bond is formed by interac...

This paper describes ab initio electronic structure calculations on the planar transition states of 2-chloropropene leading to HCl elimination in the ground electronic state to form either propyne or allene as the cofragment. The calculations provide optimized geometries of the transition states for these two reaction channels, together with vibrational frequencies, barrier heights, and reactio...

Radicals resulting from one-electron reduction of (N-methylpyridinium-4-yl) methyl esters have been reported to yield (N-methylpyridinium-4-yl) methyl radical, or N-methyl-γ-picoliniumyl for short, by heterolytic cleavage of carboxylate. This new reaction could provide the foundation for a new structural class of bioreductively activated, hypoxia-selective antitumor agents. N-methyl-γ-picoliniu...

The IR low-temperature Ar and Kr matrix spectra of l-isoserine were registered for the first time and interpreted by means of the anharmonic DFT frequencies calculated at the B3LYP/aug-cc-pVTZ and B3LYP/aug-cc-pVDZ levels. 54 l-isoserine conformers were predicted to be stable at the B3LYP/aug-cc-pVDZ level. Population of the 8 most stable conformers was based on the QCISD/aug-cc-pVDZ energies, ...

The results of a theoretical study of the one-, two- and three-water hydrolyses of carbodiimide and the one- and two-water hydrolyses of methyleneimine are presented. All structures were optimized and characterized at the MP2(full)/6-31G* level of theory. Energies for the one-water hydrolysis of carbodiimide were determined at numerous higher levels of theory, up to the QCISD(T)(fc)/6-311+G(3df...

Herein we present an assessment to determine which of nine well-established DFT functionals best describes the reduction of C2H2Se2(-)˙. In addition, we have also studied the effects of changing the substituents bound to the alkene functional group of dithiolene and diselenolene ligands. Such ligands are important due to their unique electrochemical and physical properties when ligated to metal...