A fully relativistic, ab initio quantum mechanical treatment
of many-electron systems is much more demanding than a non-relativistic
one. Relativistic effects are of considerable importance in the
chemistry of heavy atoms, e.g. in catalytic action in the third
row of transition metals. However, there are no general purpose codes
that treat multi-atom systems at the ab initio relativistic
level. Virtually all calculations employ effective potentials to approximate
relativistic effects within a non-relativistic formalism.
Although such effective potentials work well in many instances,
their validity cannot be predicted in advance, and it would be
highly desirable to have a fully relativistic methodology
to treat critical cases. Under a Cooperative Research and Development
Agreement with the Power Parallel Systems Division of the
IBM Corp., we are developing a
parallel relativistic electronic structure code for atoms. IBM
researchers will be using similar techniques to develop a relativistic
molecular astructure code.