# 6.4.1.4.6. excitoncoupling

Exciton couplings from serialized orbital files The following table contains the defaults input options for the calculator, The default OPTIONAL means this option is switched off, if no input is given. REQUIRED arguments have to be specified, otherwise an error is thrown.

Property Name | Default Value | Description | Valid Input
--- | --- | --- | ---
job_name | system | Output file name without extension, also used for intermediate files |
use_classical | false | Calculate Couplings from classical charges instead of ab-initio | bool
mpsA | A.mps | classical transition charges for segment A |
mpsB | B.mps | classical transition charges for segment B |
bsecoupling.spin | all | Spin type for couplings | singlet triplet all
bsecoupling.degeneracy | 0 | Criterium for the degeneracy of two levels | float
bsecoupling.use_perturbation | true | Output coupling via perturbation theory as value | bool
bsecoupling.moleculeA.states | 5 | Number of excitons considered | int+
bsecoupling.moleculeA.occLevels | 5 | occupied levels for CTstates | int+
bsecoupling.moleculeA.unoccLevels | 5 | unoccupied levels for CTstates | int+
bsecoupling.moleculeB.states | 5 | Number of excitons considered | int+
bsecoupling.moleculeB.occLevels | 5 | occupied levels for CTstates | int+
bsecoupling.moleculeB.unoccLevels | 5 | unoccupied levels for CTstates | int+
orbitalsA | A.orb | Serialized orbitals file |
orbitalsB | B.orb | Serialized orbitals file |
orbitalsAB | AB.orb | Serialized orbitals file |

Note

An xml file containing the defaults for the excitoncoupling calculator can be created via -p excitoncoupling -o FILENAME command line options `