(spinw-single-ion)=

# spinw.single_ion property

## Sub fields
 
`aniso`
: Row vector that contains $n_{magatom}$ integers, each integer
  assignes one of the matrices from the [spinw.matrix](#spinw-matrix) property
  to a magnetic atom in the generated [spinw.matom](#spinw-matom) list as a single
  ion anisotropy. Zero value of `aniso` means no single ion
  anisotropy for the corresponding magnetic atom.
 
`g`
: Row vector with $n_{magatom}$ integers, each integer
  assignes one of the matrices from the [spinw.matrix](#spinw-matrix) property
  to a magnetic atom in the spinw.matom list as a
  g-tensor. Zero value of `g` means a default g-value of 2 for
  the corresponding atoms.
 
`field`
: External magnetic field stored in a row vector with 3 elements,
  unit is defined in [spinw.unit](#spinw-unit) (default unit is Tesla).
 
`T`
: Temperature, scalar, unit is defined in [spinw.unit](#spinw-unit) (default
  unit is Kelvin).