anas2mat.m

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Converts anisotropy and asymmatry representation of a 3x3 interaction tensor into the corresponding matrix.

Syntax

    M=anas2mat(iso,an,as,alp,bet,gam)

Description

Isotropic part, anisotropy, and asymmetry are often seen in the literature. It is not a good way of reporting an interaction tensor (the original matrix is best), but it is still being used.

Arguments

       iso  - isotropic part of the interaction, defined as
              (xx+yy+zz)/3 in terms of eigenvaues

        an  - interaction anisotropy, defined as zz-(xx+yy)/2
              in terms of eigenvalues

        as  - interaction asymmetry, defined as (yy-xx)/(zz-iso)
              in terms of eigenvalues
 
       alp  - alpha Euler angle in radians

       bet  - beta Euler angle in radians

       gam  - gamma Euler angle in radians

Outputs

    M  - 3x3 matrix

Notes

The reverse transformation (from matrix into anisotropy, asymmetry, and angles) is ill-defined.

See also

eeqq2nqi.m, castep2nqi.m, euler2dcm.m, xyz2dd.m, spsk2mat.m, axrh2mat.m


Version 2.1, authors: Ilya Kuprov