Hund file

This file determines the coefficients of the Hund couplings given by

(2.7)\[\mathcal{H} = -\sum_{i,j}J_{ij}^{\rm Hund} (n_{i\uparrow}n_{j\uparrow}+n_{i\downarrow}n_{j\downarrow}) .\]

An example of the file format is presented below.

======================
NHund 6
======================
========Hund ======
======================
   0     1 -0.250000
   1     2 -0.250000
   2     3 -0.250000
   3     4 -0.250000
   4     5 -0.250000
   5     0 -0.250000

File format

  • Line 1: Header

  • Line 2: [nhund] [count]

  • Lines 3-5: Header

  • Lines 6-: [i] [j] [val]

Parameters

  • [nhund]

    Type : String (blank is not allowed)

    Description : An arbitrary keyword for the total number of the Hund couplings.

  • [count]

    Type : Integer (blank is not allowed)

    Description : An integer giving the total number of the Hund couplings.

  • [i], [j]

    Type : Integer (blank is not allowed)

    Description : An integer giving a site index (\(0 \le i, j < {\rm Nsite}\)).

  • [val]

    Type : Float (blank is not allowed)

    Description : A value for \(J_{ij}^{\rm Hund}\).

Usage rules

  • Headers cannot be omitted.

  • The program is terminated with error if there are duplicated entries.

  • The program is terminated with error when the number of entries is different from [count].

  • The program is terminated with error if [i] or [j] are outside the range of the defined values.