Self-consistent reaction field external fields

However, another study concluded that the changes of the hydrogen-bond stability may be important in biological processes. For these, the influence of local electric fields created by Li+, Na+, and Mg2+ ions on the properties and reactivity of hydrogen bonds in HF and HC1 dimer has been carried out by means of ab initio self-consistent field (SCF) method [33]. A few years later, the effect of intensity and vector direction of the external electric field on activation barriers of unimole-cular reactions were studied using the semiempirical MINDO/3 method [34]. However, both semiempirical and ab initio calculations were performed to study the multiplicity change for carbene-like systems in external electric fields of different configurations (carbene and silylene) and the factor that determines the multiplicity and hence the reactivity of carbene-like structures is the nonuniformity of the field [35]. 

As shown by Equations (2.189)—(2.191) the procedure briefly sketched above allows us to take into account all the effects of the solvent, both those intrinsic, i.e. due to the reaction potential, and the others related to the presence of the external field, in a compact and self-consistent form. In this way no a posteriori corrections, such as those usually introduced by cavity factors, are required, but the computed properties can be used as they are and introduced in the expressions linking the microscopic to the macroscopic. 

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