Input Data

Mandatory input

The JEDI analysis requires three pieces of input: (1) The geometry and energy of the relaxed molecule, generated by standard quantum chemical geometry optimization techniques, a mechanically deformed geometry and its energy (2) and the Hessian at the relaxed geometry, calculated in a standard frequency calculation (3). From this information, it is possible to conduct the necessary matrix transformations and multiplications. Additionally the JEDI Analyis calculates a strain energy based on the harmonic approximation. To evaluate the applicability of the harmonic approximation, the program takes the two ab initio energies of the relaxed and strained geometries. It then calculates the deviation of the ab initio energy difference and the strain energy calculated with the harmonic approximation.

The inputs have to be generated by the ASE module. The JEDI analysis uses the Atoms class for the geometries and VibrationsData class for the hessian.

Generating the input data:

• Geometries
• Hessian