# COORDINATES

### From FEFF

*Useful*

COORDINATES i Useful

i must be an integer from 1 through 6. It specifies the units of the atoms of the unit cell given in the ATOMS card for reciprocal space calculations. If the card is omitted, the default value *icoord* = 3 is assumed.

- Cartesian coordinates, Angstrom units. Like feff - you can copy from a real-space feffinp file provided that your LATTICE vectors coincide with atoms in that feff.inp file.
- Cartesian coordinates, fractional units (i.e., fractions of the lattice vectors ; should be numbers between 0 and 1). Similar to feff.
- Cartesian coordinates, units are fractional with respect to FIRST lattice vector. Like SPRKKR. (default)
- Given in lattice coordinates, in fractional units. Like WIEN2k (but beware of some `funny' lattice types, e.g. rhombohedral, in WIEN2k case.struct if you're copy-pasting )
- Given in lattice coordinates, units are fractional with respect to FIRST lattice vector.
- Given in lattice coordinates, Angstrom units.

* Say that a diamond lattice has been defined as : LATTICE P 6.0 0.0 0.5 0.5 3.4. SPECTRUM INFORMATION CARDS 19 0.5 0.0 0.5 0.5 0.5 0.0 * Now the atoms can be entered as : ATOMS 0.0 0.0 0.0 1.5 1.5 1.5 COORDINATES 1 * or 6 for this example * Or another way is : ATOMS 0.0 0.0 0.0 0.25 0.25 0.25 COORDINATES 2 * or 3, 4, and 5 for this example