strongcoca

strongcoca is a tool for evaluating the combined response of several polarizable objects, typically nanoparticles or molecules, optionally in the presence of a cavity or a polarizable medium. It is provided in the form of a Python package and can handle input in the form of response functions from different sources, including time-dependent density functional theory calculations from gpaw or nwchem.

Spectra of coupled subsystems

get_started/dipolar_coupling.rst

Mie-Gans spectra

get_started/mie_gans_response.rst

Dipole correlation energies

get_started/correlation_energy_and_absorption_spectrum.rst

An introduction to strongcoca is provided in the get started section. The following snippet illustrates the calculation of the spectrum and the correlation energy of a coupled system comprising three polarizable units.

>>> cs = CoupledSystem()
>>> cs.append(PolarizableUnit(response, [0, 0, 0]))
>>> cs.append(PolarizableUnit(response, [0, 1.5, 0]))
>>> cs.append(PolarizableUnit(response, [1.5, 0, 0]))
>>> calc = CasidaCalculator(cs)
>>> excitation_energies = calc.excitations.energies
>>> energy = calc.get_correlation_energy()