next up previous contents index
Next: The m-Matrix Up: Program Relax Previous: Conversion from Internal to   Contents   Index

Conversion of Cartesian Coordinates, Gradients and Force Constants to Internals

To perform this tasks, you have to activate the interconversion mode by
$interconversion on
   cartesian --> internal   coordinate gradient hessian
Note that any combination of the three options showed is allowed! The default value is coordinate, the two other have to be switched on explicitly if desired.

You need as input data groups:

Definitions of (redundant) internal coordinates
Cartesian coordinates (for option `coordinate')
Cartesian coordinates and gradients as provided and accumulated in subsequent optimization cycles by the various gradient programs (for coordinate and gradient)
Analytical force constant matrix (as provided by the force constant program aoforce) (only if option hessian is specified). The data group $hessian (projected) may be used alternatively for this purpose.
All output will be written to the screen except for option hessian (output to data group $forceapprox)