Using the file reciprocal.inp

From FEFF

This intermediate file written by rdinp contains all the parameters for k-space calculations. The main switch is the first parameter (all are clearly labeled in the file) reci : if it's set to 0, the calculation will be done in real space and all the parameters following it are ignored. If it's set to 1, the calculation is done in reciprocal space, and all the parameters following it are read and used. This allows the advanced user some leeway ; one could eg. calculate potentials in real space and FMS in k-space by toggling this variable.

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