Density functional theory semiempirical form

Of the available methods, quantum mechanics (QM) attacks the problem at its deepest level. Moore (1972), in one edition of his physical chemistry text, says that, in principle, aU of chemistry could be calculated from the Schrbdinger equation. Then in a footnote, he adds Tn principle from the French, n prin-cipe, ouV, which means, "Non " Since that date, however, computers and programs have become more powerful, and much effort is being made to carry out quantum-mechanical calculations of the energetics of solvation of molecules and ions in various solvents. QM calculations are implemented in ab initio form at various levels of approximation, semiempirically also at various levels, and through density-functional theory. 

There is probably no other branch of computational chemistry that arouses such strong emotions as semiempirical molecular orbital (MO) theory. Early controversies between the Dewar and Pople groups about the relative merits of MINDO/3 and HF/STO-3G calculations set the scene for a schism between ab initioists" and semiempiricists that remains in a weakened form today. Perhaps symptomatic of this schism is the controversy that raged when density functional theory (DFT) methods began to make inroads into chemistry as to whether they are ab initio (good) or semiempirical (bad). The facts, also presented by the semiempirical articles in this work, are a little different. 

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