AM1* is a semiempirical molecular orbital technique in computational chemistry. The method was developed by Timothy Clark and co-workers (in Computer-Chemie-Centrum, Universität Erlangen-Nürnberg) and published first in 2003.[1][2][3]
Indeed, AM1* is an extension of AM1[4] molecular orbital theory and uses AM1 parameters and theory unchanged for the elements H, C, N, O and F. But, other elements have been parameterized using an additional set of d-orbitals in the basis set and with two-center core–core parameters, rather than the Gaussian functions used to modify the core–core potential in AM1. Additionally, for transition metal-hydrogen interactions, a distance dependent term is used to calculate core-core potentials rather than the constant term.
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Dewar, Michael J. S.; Zoebisch, Eve G.; Healy, Eamonn F.; Stewart, James J. P. (1985). "Development and use of quantum mechanical molecular models. 76. AM1: A new general purpose quantum mechanical molecular model". J Am Chem Soc. 107 (13): 3902–3909. doi:10.1021/ja00299a024.
^Clark T, Alex A, Beck B, Chandrasekhar J, Gedeck P, Horn AHC,
Hutter M, Martin B, Rauhut G, Sauer W, Schindler T, Steinke T (2005)
Computer-Chemie-Centrum. Universität Erlangen-Nürnberg, Erlangen