Powder 5

Data

No data file loaded.

Structural Parameters

Space Group

Group unspecified

Background (Spline)

Auto-points

20

Fit background

Show Points on Chart

Excluded Regions

2θ intervals the refinement ignores: a sample-holder line, a detector artefact, a known impurity peak, the beam-stop shadow. The points inside a region are removed from the fit, so they contribute to no residual, no R factor and no degree of freedom. They are still drawn, shaded on the chart, so what was removed stays visible.

Ctrl‑Shift‑drag across the chart to add a region by eye. The other chart gestures are untouched: Ctrl‑click still places a background point, Shift‑ or Alt‑drag pans, and a plain drag zooms.

Apply exclusions

From To °

Nothing excluded; the fit uses the whole 2θ range.

Instrumental Parameters

Zero (°)

Radiation 1 (Å)

Radiation 2 (Å)

Ratio (I₂/I₁)

Polarisation

Mono. 2θM (°)

Solves the structure from the Pawley-extracted intensities by dual-space Charge Flipping. The selected space group is applied inside the iteration: orbits are generated from its real symmetry operators, systematic absences are held at zero, and symmetry equivalents are constrained to equal |F|. Only reflections that genuinely overlap in 2θ share their intensity.

Grid Size (N³) Threshold (δ / σ) Max Iterations

2000

Random Starts

3

Peak Merge (Å) Symmetry in loop Weak classification Weak Fraction

0.15

Overlap (°2θ)

Solution

Electron-density peaks

Fractional coordinates in P1. The origin and the hand of the solution are arbitrary — compare interatomic distances, not absolute positions. “Nearest peak” is the distance to the closest other peak in this list: it says how isolated each peak is, and is neither a resolution limit nor a bond length. A value far below any real bond means the peak is a ripple beside a stronger neighbour, not an atom of its own.

#	x	y	z	Height	Charge	Nearest peak (Å)

Density section

– 0 –

–

Axis Section

–

Stretch each slice to its own range

3D isosurface

–

Map Level (σ)

–

Unit cell edges

Atom positions

Structure

Built automatically at the end of every run, or via Wyckoff search: finds the origin shift that makes the map obey the space-group operators, averages over them, and reduces the peaks to one site per orbit with its multiplicity.

–

#	x	y	z	Mult	Height

Fits atoms on Wyckoff positions of the given composition directly to the Pawley intensities. The objective is |F_calc|² against the observed intensities, weighted by 1/σ².

Formula Z Max reuse / pos Max sites / elem

Density min (g/cm³)

2

Density max (g/cm³)

10

Max Z searched

3

Chains

512

Iterations

2000

Restarts

4

Min contact (Å)

Distance constraints

Enter a target composition above to enable the search.

Asymmetric Unit

Pattern

Step (°2θ)

Background

Noise (× counts)

Max intensity

Match data scale to tallest peak

The 2θ range, the wavelengths, the zero point and the peak shape are the ones set on the Sample and Profile tabs, so a simulation and a fit of the same model are computed through exactly the same profile.

Method

Method Max Iterations

20

2θ min (°)

2θ max (°)

Rp (%)

-

Rwp (%)

-

χ² (GOF)

-

Awaiting Data

Load a data file to begin.

Le Bail run history

Run:

No Le Bail run yet. Results appear here after each fit.

Pawley run history

Run:

No Pawley run yet. Results appear here after each fit.

Charge Flipping run history

Run:

No Charge Flipping run yet. Results appear here after each run.

Wyckoff search

Run:

No Wyckoff search yet. Results appear here after each run.

Data

Structural Parameters

Background (Spline)

Excluded Regions

Gaussian Broadening

Lorentzian Broadening

Peak Shape & Position

Isotropic Gaussian (TCH)

Isotropic Lorentzian (TCH)

Peak Asymmetry

Anisotropic Broadening (Stephens)

Gaussian (Left Side)

Gaussian (Right Side)

Lorentzian (Left Side)

Lorentzian (Right Side)

Peak Shape

Instrumental Parameters

Solution

Electron-density peaks

Density section

3D isosurface

Structure

Asymmetric Unit

Pattern

Method

Powder 5 Fit

Supported File Formats:

Chart Interaction:

Awaiting Data

Le Bail run history

Pawley run history

Charge Flipping run history

Wyckoff search

Session log