example.htm

Example Input Files

Example Input File for "File 1"

To understand the construction of the input files, let us take the example of a {Mn₆} coordination complex shown in the figure below. [Tandon]

Structure of the {Mn₆} complex. Colour scheme: Mn (dark blue), P (pink), Cl (green), C (black), N (blue) and O (red). Hydrogen atoms have been removed for clarity.

The Mn centres in this complex interact with each other via the phosphonate ligands and the central Cl^- ion. Each Mn centre in this complex has 1 trans- and 4 cis- neighbours and one requires 2 J-values to account for these cis- and trans- interactions between Mn centres.[Tandon] Therefore, the Hamiltonian for this complex can written as follows:

    Ĥ = -2J₁[<s₁.s₄> + <s₂.s₅> + <s₃.s₆>] -2J₂[<s₁.s₂> + <s₁.s₃> + <s₁.s₅> + <s₁.s₆> + <s₂.s₃> + <s₂.s₄> + <s₂.s₆> + <s₃.s₄> + <s₃.s₅> + <s₄.s₅> + <s₄.s₆> + <s₅.s₆>]

This Hamiltonian can be represented using the following input file:

magnetic centres
6
J values
2
Hamiltonian
1 4
3 6
2 5
****
1 2
1 3
1 5
1 6
2 3
2 4
2 6
3 4
3 5
4 5
4 6
5 6
Hamiltonian Ends

Example Input File for "File 2"

The following is an example spin operator file for the above mentioned Mn₆ system. The spin operators were obtained using Bader population analysis and the energy was obtained from DFT calculations.[Tandon] The first six numbers on each line represent the spin density on each of the six Mn centre in a given spin configuration and the last number on the line represents the energy of the corresponding state in Hartrees.

-3.7863320 3.7861321 3.7863107 3.7868157 -3.7862305 -3.7862343 -8.605807229691483E+03
-3.7861476 3.7886816 3.7866279 3.7867024 3.7888073 -3.7859959 -8.605807007350464E+03
-3.7885975 3.7885472 3.7866686 -3.7885253 3.7885196 -3.7865706 -8.605806946257479E+03
-3.7883188 3.7884830 3.7887427 -3.7882102 3.7889254 3.7890060 -8.605806714840277E+03
-3.7861387 3.7889810 3.7892562 3.7871543 3.7892340 3.7891449 -8.605806609885272E+03
3.7890715 3.7894288 3.7894591 3.7895166 3.7895544 3.7891216 -8.605806049221312E+03

The energies are given here in scientific notation but they can be in non-scientific notation too.

These example input files and the resultant output file have also been provided as separate files in the package along with other examples.