CPCM conductor-like polarizable continuum

CPCM conductor-like polarizable continuum model... 

M06/6-31-l-l-G calculations in the gas phase and using the CPCM (conductor-like polarizable continuum model) in solution have shown that the formal reaction of imidozirconocene with allylic ethers and an imidotitanium complex with allylic alcohols occurs by a [2 -I- 2] cycloaddition/retro- [2 -I- 2] pathway via central transition states rather than by the proposed [3,3] sigmatropic rearrangement mechanism. ... 

CPCM Conductor-like Polarizable Continuum model... 

Keeping in mind the intrinsic features associated with the definition of the cavity in the most popular QM-SCRF methods, it can be questioned what is the influence of the fine details of the cavity definition on the computed solvation free energies. This question has been investigated in a recent study by Takano and Houk [61], who have examined the dependence of the solvation free energies estimated for a series of 70 compounds, including neutral and charged species, on both the choice of the cavity and the level of theory used in computations within the framework of the conductor-like polarizable continuum model (CPCM). The mean absolute deviation (MAD) between calculated... 

Y. Takano and K. N. Houk, Benchmarking the conductor-like polarizable continuum model (CPCM) for aqueous solvation free energies of neutral and ionic organic molecules, J. Chem. Theory Comput., 1 (2005) 70-77. 

We applied the dual VFA approach to a neutral form (NF) glycine molecule in aqueous solution and compared the calculation results with those estimated by the conductor-like polarizable continuum model (CPCM) method in order to extract the explicit solvation effects. Table 8.1 shows a triple of typical vibrational frequencies (cugas, cocpcMi coee) of glycine molecule in the isolated state and in aqueous solution with their vibrational frequency shifts, (AcocpcM) Acofe). evaluated by two types of solute-solvent interactions, i.e., the CPCM and QM/MM method, scaled by the recommended factor of 0.9418 [43]. In addition, they were compared with the experimental values Acoexp obtained by the Fourier transform infrared (FT-IR)... 

In 1999, Quast found dipolar and polarizable solvents such as lV,iV -dimethylprop-ylene urea (DMPU) strongly affect and even may reverse the relative stabilities of the localized and delocalized structures of 4,8-diphenylsemibullvalene-2,6-dicarboni-trile. The author calculated electrical dipole and quadrupole moments and molecular polarizabilities using the B3LYP/6-31G method and computed solvation energies with the conductor-like polarized continuum model (CPCM). The results indicate that the solvent effects are due to the greater polarity and polarizability of the delocalized structures relative to the localized structures (Fig. 4.10) [10]. 

For solvation of small molecules, the polarizable continuum model (PCM) and its variants have been widely used for calculation of solvation energy. The conductor-like PCM (CPCM) model gives a concise formulation of solvent effect, in which the solvent s response to the solute polarization is represented by the presence of induced surface charges distributed on the solute-solvent interface. In this formulation, no volume polarization (extension of solute s electron distribution into the solvent region) is allowed. The induced surface charge counterbalances the electrostatic potential on the interface generated by the solute molecule. 

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