Avm. Deandrade et al., SPARKLE MODEL FOR THE QUANTUM-CHEMICAL AM1 CALCULATION OF EUROPIUM COMPLEXES, Chemical physics letters, 227(3), 1994, pp. 349-353
Considering that the bonds between a lanthanide and its ligands essent
ially possess an electrostatic character, we propose the representatio
n of rare-earth elements within AM 1 as sparkles. To parametrize the s
parkle model we have used the known geometry of the complex tris (acet
ylacetonate) (1,10-phenantroline) of europium (III). Interatomic dista
nces for the coordination polyhedron, averaging 2.81 angstrom, could b
e predicted with an average deviation of 0.13 angstrom. In short, this
is a simple lanthanide-ligand electrostatic model which simultaneousl
y treats the organic ligands and their interactions with the powerful
AM1 method, yielding results of useful accuracy.