occ::crystal::PowderPattern Class Reference

A simulated powder X-ray diffraction pattern. More...

#include <powder.h>

Public Member Functions
	PowderPattern (std::vector< PowderPeak > peaks, double wavelength)
const std::vector< PowderPeak > &	peaks () const
	The peaks, sorted by increasing 2*theta.
double	wavelength () const
size_t	size () const
Vec	normalized_intensities () const
	Peak intensities rescaled so that the strongest peak is 100.
std::pair< Vec, Vec >	profile (double two_theta_min, double two_theta_max, int num_bins=4500, double fwhm=0.1) const
	Bin the peaks onto a 2*theta grid and broaden them.

Detailed Description

A simulated powder X-ray diffraction pattern.

Intensities use neutral-atom X-ray form factors (International Tables 1992), Debye-Waller factors from the structure's ADPs, and the Lorentz-polarization factor.

Not modelled: anomalous dispersion (f', f''), the K-alpha_1 / K-alpha_2 doublet, preferred orientation, peak asymmetry, and 2*theta-dependent broadening. Intensities are therefore most reliable for light atoms away from an absorption edge.

Constructor & Destructor Documentation

PowderPattern()

occ::crystal::PowderPattern::PowderPattern	(	std::vector< PowderPeak >	peaks,
		double	wavelength
	)

Member Function Documentation

normalized_intensities()

Vec occ::crystal::PowderPattern::normalized_intensities

(

)

const

Peak intensities rescaled so that the strongest peak is 100.

peaks()

const std::vector< PowderPeak > & occ::crystal::PowderPattern::peaks ( ) const

inline

The peaks, sorted by increasing 2*theta.

Systematically absent reflections are not included, and coincident reflections have been merged.

profile()

std::pair< Vec, Vec > occ::crystal::PowderPattern::profile	(	double	two_theta_min,
		double	two_theta_max,
		int	num_bins = 4500,
		double	fwhm = 0.1
	)		const

Bin the peaks onto a 2*theta grid and broaden them.

Parameters

two_theta_min	lower edge of the grid, in degrees
two_theta_max	upper edge of the grid, in degrees
num_bins	number of grid points
fwhm	full width at half maximum of the Gaussian, in degrees. A value <= 0 disables broadening (a raw histogram).

Returns

a pair of (bin centres, intensities)

size()

size_t occ::crystal::PowderPattern::size ( ) const

inline

wavelength()

double occ::crystal::PowderPattern::wavelength ( ) const

inline

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The documentation for this class was generated from the following file:

• /home/runner/work/occ/occ/include/occ/crystal/powder.h