Magneticfield densityfunctional theory
Abstract
We discuss the formal basis and general advantages of magneticfieldanddensity functional theory (BDFT) for the groundstate magnetic properties of manyelectron systems. The groundstate density ρ(r) and the magnetic field B(r) are the variables appearing in the energy functionals that are the fundamental elements of BDFT. This is in contrast to the energy functionals of currentanddensity functional theory (CDFT), the most general densityfunctional way of treating systems in a magnetic field, where the variables are ρ(r) and the groundstate paramagnetic current j_{p}(r). Explicit calculations of magnetic properties have already been made that can be recognized as belonging to the BDFT paradigm, which this work therefore puts on a formal foundation. There are also aspects of BDFT discussed here that may make it an attractive alternative to the more general CDFT in some situations. In particular, we show that KohnSham equations may be derived that use purely real orbitals and for which the energy does not separate into para and diamagnetic contributions. We also show that in BDFT the zerofield electron density alone is sufficient to calculate the energy to second order in the magnetic field. Thus calculation of, e.g., diamagnetic susceptibilities or chemical shifts can in principle be made directly from zerofield electron distributions, without any need for the calculation of firstorder corrections.
 Publication:

Physical Review A
 Pub Date:
 October 1994
 DOI:
 10.1103/PhysRevA.50.3089
 Bibcode:
 1994PhRvA..50.3089G
 Keywords:

 31.20.Sy;
 41.20.Gz;
 31.20.Lr;
 33.25.Dq;
 Magnetostatics;
 magnetic shielding magnetic induction boundaryvalue problems