vibanal.cc File Reference

#include <madness/chem/vibanal.h>
#include <madness/tensor/tensor_lapack.h>

Include dependency graph for vibanal.cc:

Functions
Tensor< double >	compute_frequencies (const Molecule &molecule, const Tensor< double > &hessian, Tensor< double > &normalmodes, const bool project_tr, const bool print_hessian)
	returns the vibrational frequencies
Tensor< double >	compute_reduced_mass (const Molecule &molecule, const Tensor< double > &normalmodes)
Tensor< double >	projector_external_dof (const Molecule &mol)
	compute the projector to remove transl. and rot. degrees of freedom
void	remove_external_dof (Tensor< double > &hessian, const Molecule &mol)
	remove translational degrees of freedom from the hessian

Function Documentation

compute_frequencies()

Tensor< double > compute_frequencies	(	const Molecule &	molecule,
		const Tensor< double > &	hessian,
		Tensor< double > &	normalmodes,
		const bool	project_tr,
		const bool	print_hessian
	)

returns the vibrational frequencies

Parameters

[in]	hessian	the hessian matrix (not mass-weighted)
[out]	normalmodes	the normal modes
[in]	project_tr	whether to project out translation and rotation
[in]	print_hessian	whether to print the hessian matrix

Returns

the frequencies in atomic units

References madness::inner(), madness::Molecule::massweights(), molecule, madness::Molecule::natom(), madness::print(), remove_external_dof(), madness::BaseTensor::size(), and madness::syev().

Referenced by madness::Nemo::hessian().

compute_reduced_mass()

Tensor< double > compute_reduced_mass	(	const Molecule &	molecule,
		const Tensor< double > &	normalmodes
	)

References madness::constants::atomic_mass_in_au, madness::copy(), madness::inner(), L, madness::Molecule::massweights(), molecule, mu, madness::Molecule::natom(), and projector_external_dof().

Referenced by madness::Nemo::hessian().

projector_external_dof()

Tensor< double > projector_external_dof

(

const Molecule &

mol

)

compute the projector to remove transl. and rot. degrees of freedom

taken from http://www.gaussian.com/g_whitepap/vib.htm I don't really understand the concept behind the projectors, but it seems to work, and it is not written down explicitly anywhere. NOTE THE ERROR IN THE FORMULAS ON THE WEBPAGE !

References madness::_(), madness::constants::atomic_mass_in_au, madness::Molecule::center_of_mass(), e(), madness::Molecule::get_atom(), madness::Atom::get_mass_in_au(), I, madness::inner(), madness::Molecule::moment_of_inertia(), madness::Molecule::natom(), norm(), madness::Tensor< T >::normf(), p(), madness::Tensor< T >::scale(), madness::syev(), madness::Molecule::translate(), madness::transpose(), v, madness::Atom::x, madness::Atom::y, and madness::Atom::z.

Referenced by compute_reduced_mass(), and remove_external_dof().

remove_external_dof()

void remove_external_dof	(	Tensor< double > &	hessian,
		const Molecule &	mol
	)

remove translational degrees of freedom from the hessian

References madness::inner(), and projector_external_dof().

Referenced by compute_frequencies().