Formyloxyl radical

A. D. McLean, B. H. Lengsfield, III, J. Pacansky, Y. Ellinger, J. Chem. Phys. 83, 3567 (1985). Symmetry Breaking in Molecular Calculations and the Reliable Prediction of Equilibrium Geometries. The Formyloxyl Radical as an Example. 

A series of 28 stable molecules and 12 radicals containing the groups listed in table 4.1 are calculated and reported below. For these calculations, enthalpy values for standard reference species are needed in the working reactions. In some cases the enthalpy value of a reference molecule is also determined from own calculation. Since no reliable literature data was available, the propenoxyl radical CH2=CHC(0 )=0 and formyloxyl radical CH(0 )=0 used as reference species were estimated with the following isodesmic reactions ... 

There are many molecules, in particular some radicals, that are naturally described in terms of two or more resonance structures, and for which the one-configuration approximation is not appropriate. Such molecules are generally subject to the well-known broken-symmetry artifact, whereby a wave function calculated at an insufficient level of theory is of lower symmetry than the nuclear framework, which results in erroneous energetics and discontinuities of the calculated potential surface. The formyloxyl radical (42 43 in Scheme 20) is a typical example, but the problem is very general and includes... 

MCSCF/CI Investigation of the Low-lying Potential Energy Surfaces of the Formyloxyl Radical, HCO2. 

Symmetry Breaking in Molecular Calculations and the Reliable Prediction of Equilibrium Geometries. The Formyloxyl Radical as an Example. 

This is 1.8 eV below the entrance channel. In order to confirm that this is a relative minimum with respect to the absolute minimum at C2v geometries of the formyloxyl radical, we have carried out a few calculations by relaxing the OH bond length around the relative minimum position. It is found that while the energy of the 2 A and l A" states increases, in contrast the X A state quickly drops to its C2v minimum, found previously [14,15]. Although we have not done an extensive minimization search around the minimum of the 2 A surface, our calculations do not show any route with a low barrier for the system to pass to the absolute C2v minimum of 2 A. ... 

Radicals. Formyloxyl (HCOO) and Acetoxyl (CH3OO) Revisited. 

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