RECENT DEVELOPMENTS IN THE METHOD OF SQM FORCE-FIELDS WITH APPLICATION TO 1-METHYLADENINE

The method of Scaled Quantum Mechanical (SQM) force fields has been re viewed briefly and recent developments to make its use more automatic discussed. Essential features are the definition of internal coordinat es by a computer program and also a first version of assigning scale f actors automatically. SQM calculations have been applied on three taut omers of the title molecule. Completely optimized geometries include r esults also with a large basis set, 6-311G(d, p). We find no convincin g evidence far the presence of any other tautomer than the N9H imino f orm. (C) 1997 Elsevier Science B.V.