Self-consistent field acronyms

At the energy minimum, each electron moves in an average field due to the Other electrons and the nuclei. Small variations in the form of the orbitals at this point do not change the energy or the electric field, and so we speak of a self-consistent field (SCF). Many authors use the acronyms HF and SCF interchangeably, and I will do so from time to time. These HF orbitals are found as solutions of the HF eigenvalue problem... 

Quantum Mechanics and Molecular Mechanics. It is a general acronym for the hybrid method Self-Consistent Field... 

In brief, the CNDO (the acronym stands for complete neglect of differential overlap) approach is an all valence electron, self-consistent field calculation in which multicenter integrals have been neglected and some of the two electron integrals parameterized using atomic data. Slater type atomic orbitals are used as the basis 2s, 2px, 2p, 2p for carbon and oxygen. In these calculations two-electron in egrafs are approximated as... 

The CURES-EC method was named because it CURES the ELECTRON CORRELATION problem in semi-empirical calculations. This is accomplished by adding multiconfiguration configuration interaction (MCCI) to the wave functions. The acronym CURES-EC stands for configuration interaction or unrestricted orbitals to relate experimental electron affinities to self-consistent field values by estimating electron correlation. Electron affinities of radicals can be obtained from experimental gas phase acidities by calculating C—H bond dissociation... 

If you want to explore the design features of the various spreadsheets in detail, you will need to change the spreadsheets into unprotected form. Protection levels on open files are set in the TOOLS dialogue box and the universal password for the files on the CD is hfsscf. This acronym is formed from Hartree-Fock-Slater-Self-Consistent-Field. 

Instead of optimization of all the orbitals, only the active orbitals will be varied within the Complete Active Space Self-Consistent Field approximation (CASSCF). In the acronym of this method, the number of active orbitals and active electrons are also provided for the given system. For instance, CASSCF(6,4) denotes the calculations with the expansion including all the possible exchanges of the four electrons within the six active orbitals. The CASSCF approach leads to all possible exchanges in the given active space, and for a moderately sized system, the size of the active spaces can quickly exceed the computational resources. In such a case, the solution can be the Restricted Active Space Self-Consistent Field method (RASSCF), which supplies a way of limiting the size of the active space. 

The acronym SCRF is the contraction of two different acronyms, SCF and SRF. The former, SCF self-consistent field) is used in quantum mechanics (QM) to denote methods that give the best description of the electronic wave function of the system (atom, molecule, etc.) in terms of the minimal number of antisymmetrized products of one-electron functions, the molecular orbitals (MOs). A synonym of SCF is HF (Hartree-Fock), an acronym also used to indicate the Hamiltonian of the system in this approximation. 

During the last 40 years it has been possible to witness an important evolution on the way the environment around a solute molecule is described. The reaction field approach, the effect a continuous dielectric medium has on the charge distribution of a molecule that polarizes back the dielectric and generates a reaction potential, is a standard scheme to consider the solvent effects on many molecular properties. Most modem continuum models obtain through a self-consistent cycle the wave function of the molecule affected by the reaction potential thus the self-consistent reaction field acronym (SCRF). Solvatochromic effects have been more or less successfully explained using from Onsager s to more refined models like Nancy SCRF [44], Tomasi s polarizable continuum model (PCM) [45], Cramer and Tmhlar s SMx models [46]. 

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