Package etomica.normalmode

Class NormalModesPotential

java.lang.Object

etomica.normalmode.NormalModesPotential

All Implemented Interfaces:

NormalModes

public class NormalModesPotential
extends java.lang.Object
implements NormalModes

Uses analysis of 2nd derivatives to compute the normal modes for a Bravais lattice with a basis, occupied by atoms that interact with a simple, spherically-symmetric soft potential.

Field Summary

Fields

Modifier and Type	Field	Description
protected Space	space

Constructor Summary

Constructors

Constructor	Description
NormalModesPotential(int[] nCells, Primitive primitive, Basis basis, Potential2SoftSpherical potential, Space space)

Method Summary

Modifier and Type	Method	Description
void	calculateModes()
double[][][]	getEigenvectors()	First index corresponds to the wave vector; second index gives the eigenvector, and third index gives the elements of the vector.
java.lang.String	getFileName()
int	getMaxLatticeShell()
double[][]	getOmegaSquared()	Returns an array giving the frequencies (squared) corresponding to the normal-mode motions.
WaveVectorFactory	getWaveVectorFactory()	Returns a factory that provides the wave vectors and coefficients for the periodic system.
void	setFileName(java.lang.String filename)
void	setHarmonicFudge(double newHarmonicFudge)	Set the fudge factor applied to frequencies.
void	setMaxLatticeShell(int maxLatticeShell)
void	setPotential(Potential2SoftSpherical potential)
void	setTemperature(double newTemperature)	Set the temperature used for calculating omega-squared.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

space

protected final Space space

Constructor Detail

NormalModesPotential

public NormalModesPotential(int[] nCells,
                            Primitive primitive,
                            Basis basis,
                            Potential2SoftSpherical potential,
                            Space space)

Method Detail

calculateModes

public void calculateModes()

setPotential

public void setPotential(Potential2SoftSpherical potential)

getEigenvectors

public double[][][] getEigenvectors()

Description copied from interface: NormalModes

First index corresponds to the wave vector; second index gives the eigenvector, and third index gives the elements of the vector. Length of 2nd and 3rd dimensions is coordinateDim.

Specified by:

getEigenvectors in interface NormalModes

getOmegaSquared

public double[][] getOmegaSquared()

Description copied from interface: NormalModes

Returns an array giving the frequencies (squared) corresponding to the normal-mode motions. First index indicates the wave vector, and second index indicates the eigenvector. Length of second index is coordinateDim.

Specified by:

getOmegaSquared in interface NormalModes

getWaveVectorFactory

public WaveVectorFactory getWaveVectorFactory()

Description copied from interface: NormalModes

Returns a factory that provides the wave vectors and coefficients for the periodic system.

Specified by:

getWaveVectorFactory in interface NormalModes

getMaxLatticeShell

public int getMaxLatticeShell()

setMaxLatticeShell

public void setMaxLatticeShell(int maxLatticeShell)

setHarmonicFudge

public void setHarmonicFudge(double newHarmonicFudge)

Description copied from interface: NormalModes

Set the fudge factor applied to frequencies. The squared-frequencies returned by getOmegaSquared will be the nominal values divided by the given fudge factor. Thus a smaller value of this fudge factor will make for "tighter" harmonic springs, corresponding to to smaller deviation from the lattice sites.

Specified by:

setHarmonicFudge in interface NormalModes

setTemperature

public void setTemperature(double newTemperature)

Description copied from interface: NormalModes

Set the temperature used for calculating omega-squared. Omega-squared is kT/eigenvalue.

Specified by:

setTemperature in interface NormalModes

getFileName

public java.lang.String getFileName()

setFileName

public void setFileName(java.lang.String filename)