Effect of Fock exchange on the electronic structure and magnetic coupling in NiO

被引:295
作者
Moreira, IDR
Illas, F
Martin, RL
机构
[1] Univ Barcelona, Dept Quim Fis, E-08028 Barcelona, Spain
[2] Univ Barcelona, Ctr Recerca Quim Teor, E-08028 Barcelona, Spain
[3] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA
关键词
D O I
10.1103/PhysRevB.65.155102
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The effect of Fock exchange on the periodic description of the geometrical structure, elastic constants, and electronic and magnetic properties of NiO is analyzed. Hybrid density functionals which combine a portion of "exact" Fock exchange with conventional local density approximation (LDA) or generalized gradient approximation (GGA) functionals remedy a number of serious inconsistencies with the traditional LDA or GGA descriptions of this prototypical "Mott" insulator. For example, the hybrid B3LYP functional (which mixes similar to20% Fock exchange with GGA functionals) introduces a significant insulating gap and yields antiferromagnetic Heisenberg coupling constants between Ni sites (J(2)) in semiquantitative agreement with experiment. Closer inspection shows that while the B3LYP orbital band gap is in excellent agreement with experiment, the magnitude of the antiferromagnetic coupling is overestimated by slightly more than 50%. This has led us to examine a simplified model which combines Fock exchange with the LDA exchange and correlation functionals. This combination allows us to study the magnitude and nature of the band gap, the magnitude of the unpaired spin densities in the different magnetic phases, and the two most important magnetic coupling constants as a function of the fraction of Fock exchange included. It is concluded that similar to35% Fock exchange gives a reasonably balanced description of all properties, including structural parameters, magnetic form factors, the antiferromagnetic Ni-Ni exchange constant, and the character and magnitude of the band gap.
引用
收藏
页码:1551021 / 15510214
页数:14
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共 116 条
  • [1] Toward reliable adiabatic connection models free from adjustable parameters
    Adamo, C
    Barone, V
    [J]. CHEMICAL PHYSICS LETTERS, 1997, 274 (1-3) : 242 - 250
  • [2] Alperin H.A., 1962, J PHYS SOC JAPAN SB3, V17, P12
  • [3] ASPHERICAL 3D ELECTRON DISTRIBUTION IN NI++
    ALPERIN, HA
    [J]. PHYSICAL REVIEW LETTERS, 1961, 6 (02) : 55 - &
  • [4] 2ND-ORDER PERTURBATION-THEORY WITH A COMPLETE ACTIVE SPACE SELF-CONSISTENT FIELD REFERENCE FUNCTION
    ANDERSSON, K
    MALMQVIST, PA
    ROOS, BO
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1992, 96 (02) : 1218 - 1226
  • [5] 2ND-ORDER PERTURBATION-THEORY WITH A CASSCF REFERENCE FUNCTION
    ANDERSSON, K
    MALMQVIST, PA
    ROOS, BO
    SADLEJ, AJ
    WOLINSKI, K
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1990, 94 (14) : 5483 - 5488
  • [6] ANDERSSON K, 1997, COMPUTER CODE MOLCAS
  • [7] BAND THEORY AND MOTT INSULATORS - HUBBARD-U INSTEAD OF STONER-I
    ANISIMOV, VI
    ZAANEN, J
    ANDERSEN, OK
    [J]. PHYSICAL REVIEW B, 1991, 44 (03): : 943 - 954
  • [8] DENSITY-FUNCTIONAL THEORY AND NIO PHOTOEMISSION SPECTRA
    ANISIMOV, VI
    SOLOVYEV, IV
    KOROTIN, MA
    CZYZYK, MT
    SAWATZKY, GA
    [J]. PHYSICAL REVIEW B, 1993, 48 (23): : 16929 - 16934
  • [9] ELECTRONIC-STRUCTURE OF NIO IN THE GW APPROXIMATION
    ARYASETIAWAN, F
    GUNNARSSON, O
    [J]. PHYSICAL REVIEW LETTERS, 1995, 74 (16) : 3221 - 3224
  • [10] A quantum chemical view of density functional theory
    Baerends, EJ
    Gritsenko, OV
    [J]. JOURNAL OF PHYSICAL CHEMISTRY A, 1997, 101 (30) : 5383 - 5403