Semiempirical molecular orbital theory

Thiel W 1996 Perspectives on semiempirical molecular orbital theory New Methods in Computationai Quantum Meohanios (Adv. Chem. Phys. XCiti) ed I Prigogine I and S A Rice (New York Wiley) pp 703-57 Earlier texts dealing with semi-empirical methods include ... 

J. N. Murrell and A. J. Harget, Semi-empirical Self-consistent Molecular Orbital Theory of Molecules, Wiley-Interscience, London, 1972 G. H. Wagniere, Introduction to Elementary Molecular Orbital Theory and to Semiempirical Methods, Springer-Verlag, Berlin, 1976 J. Sadleij, Semi-empirical Methods of Quantum Chemistry, Wiley, New York, 1985. 

J. N. Murrell and A. J. Harget, Semiempirical Self-Consistent-Field Molecular Orbital Theory of Molecules, Wiley-Interscience, London (1972). 

How well can continuum solvation models distinguish changes in one or another of these solvent properties This is illustrated in Table 2, which compares solvation energies for three representative solutes in eight test solvents. Three of the test solvents are those shown in Table 1, one is water, and the other four were selected to provide useful comparisons on the basis of their solvent descriptors, which are shown in Table 3. Notice that all four solvents in Table 3 have no acidity, which makes them more suitable, in this respect, than 1-octanol or chloroform for modeling biomembranes. Table 2 shows that the SM5.2R model, with gas-phase geometries and semiempirical molecular orbital theory for the wave function, does very well indeed in reproducing all the trends in the data. 

G.H. Wagniere, Introduction to Elementary Molecular Orbital Theory and to Semiempirical Methods, 1976, Springer, Berlin. 

L-C. With polarizable charges obtained by semiempirical molecular orbital theory. 

Murrell, J. N., Harget, A. J. Semiempirical self-consistent-field molecular orbital theory of molecules. London Wiley-Interscience 1972. 

Thiel, W. 1998. Thermochemistry from Semiempirical Molecular Orbital Theory in Computational Thermochemistry, ACS Symposium Series, Vol. 677, Irikura. K. K. and Frurip, D. J., Eds., American Chemical Society Washington, DC, 142. 

Li, J. Cramer, and Truhlar, D. G. 1999. Application of a Universal Solvation Model to Nucleic Acid Bases. Comparison of Semiempirical Molecular Orbital Theory, Ab Initio, Hartree-Fock Theory, and Density Functional Theory , Biophys. Chem.. 78, 147. 

The AMI (8) approximation to molecular orbital theory has been used for these studies. This method overcomes the problems that previous semiempirical methods (notably, MNDO) (9) have in describing hydrogen-bonds. It has been used with success in several hydrogen-bonding studies. (10-12) Ab initio studies of H-bonding systems are very sensitive to basis set and correction for electron-... 

Thiel, W. (1998) In K.K. Irikura and D.J. Frurip (Eds) Thermochemistry from Semiempirical Molecular Orbital Theory, ACS Symposium Series (vol 677). American Chemical Society, Washington, D.C., p. 142. 

The methods available for computing enthalpies of formation fall into two general groups those based on purely empirical schemes and those founded on quantum chemistry. The quantum chemical methods can be further divided into three types ab initio molecular orbital theory, density functional theory, and semiempirical molecular orbital theory. A summary of the types of method used to calculate enthalpies of formation is given in Table 2, along with some specific examples. This is not meant to be a comprehensive tabulation, but rather a list of some of the more popular approaches in use today. Table 3 names some of the commercially available computer programs having capabilities to calculate thermochemical data. 

Semiempirical molecular orbital methods23-25 incorporate parameters derived from experimental data into molecular orbital theory to reduce the time-consuming calculation of two-electron integrals and correlation effects. Examples of semiempirical molecular orbital methods include Dewar s AMI, MNDO, and MINDO/3. Of the three quantum chemical types, the semiempirical molecular orbital methods are the least sophisticated and thus require the least amount of computational resources. However, these methods can be reasonably accurate for molecules with standard bond types. 

W. Thiel, Adv. Cbem. Phys., 93, 703 (1996). Perspectives on Semiempirical Molecular Orbital Theory. 

R.L. Flurry Jr., Molecular orbital theory of electron donor-acceptor complexes. I. A simple semiempirical treatment. J. Phys. Chem. 69, 1927-1933 (1965)... 

Lykos, P. G. The parameters used in semiempirical molecular orbital theory for conjugated hydrocarbons. J. Chem. Phys. 35, 1249 (1961). 

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