Paired Orbitals for Different Spins Equations
arXiv.org, e-Print Archive, Physics
Number: arXiv:0804.0967v1 [physics.chem-ph],
Ruzankin Sergey Ph.
Boreskov Institute of Catalysis SB RAS
Eigenvalue-type equations for Lowdin-Amos-Hall spin-paired (corresponding) orbitals are developed to provide an alternative to the standard spin-polarized Hartree-Fock or Kohn-Sham equations. Obtained equations are non-canonical unrestricted Hartree-Fock-type equations in which non-canonical orbitals are fixed to be biorthogonal spin-paired orbitals. To derive paired orbitals for different spins (PODS) equations there has been applied Adams-Gilbert localizing operator approach. PODS equations are especially useful for treatment of the broken-symmetry solutions for antiferromagnetic materials.