From Spinach Documentation Wiki
Jump to: navigation, search

Draws electric field gradient tensors and their eigensystems. Two styles are implemented:

A. Ellipsoids (symmetric tensors only)
1. A unit sphere in a Cartesian space is scaled by abs(Axx) in the x direction, abs(Ayy) in the y direction and abs(Azz) in the z direction, where Axx, Ayy, Azz are the eigenvalues of the CST tensor in units of ppm.
2. A set of axes is drawn inside the sphere with a red axis for a positive eigenvalue, and a blue axis for a negative one.
3. The sphere is translated to the point of corresponding nucleus and rotated into the molecular frame of reference.
B. Spherical harmonics (default)
1. The matrix is converted into irreducible spherical tensor operator coefficients.
2. The coefficients are placed in front of the corresponding spherical harmonics, which are plotted in three dimensions and translated to the point of the corresponding nucleus.




              props - output of c2spinach.m function

              atoms - a cell array of element symbols,
                      indicating the atoms for which
                      the EFG tensors should be visu-
                      alised, e.g. {'N','O'}

            scaling - a factor to scale the tensors
                      by for visualisation

          conmatrix - binary connectivity matrix, 1
                      if a pair of atoms should be
                      connected by a bond. If an em-
                      pty vector is supplied, 1.6 
                      Angstrom cutoff distance is used

      options.style - 'ellipsoids' or 'harmonics'

   options.kill_iso - set to true() to eliminate the
                      isotropic parts of tensors be-
                      fore plotting


The following figure is produced by /examples/visualisation/efg_silicate.m - (left) ellipsoid plot; (right) spherical harmonic plot.

Efg silicate.png


Only CASTEP quantum chemistry package is supported at the moment - send an email to Ilya Kuprov if you are using something else.

See also

hfc_display.m, cst_display.m, volplot.m, molplot.m, conmat.m, gparse.m

Version 2.7, authors: Ilya Kuprov