Absorption Coefficient Calculator
Mass and linear absorption coefficients for a chemical formula, for Ag, Mo and Cu radiation.
Crystallography calculators
Six calculators for X-ray crystallography — the arithmetic that comes up over and over at a diffractometer and in a structure report, done carefully and shown together with the assumptions it rests on.
They are meant to be useful two ways: as a working tool when you already know what you are after, and as somewhere to see what a number actually means when you are still learning. Every result has its own address, so an answer can be bookmarked, sent to a colleague or linked from a course page.
The calculators
Bragg Calculator
Convert between d-spacing and 2-theta for six K-alpha wavelengths.
HKL Calculator
Cell volume, d-spacing, 2-theta, the symmetry-equivalent reflections of a Miller index, and the powder stick pattern of the cell.
cubic – NaCl (200) · hexagonal – quartz (101) · tetragonal – rutile (110) · orthorhombic – aragonite (111) · monoclinic – zirconia (111) · triclinic – albite (111)
Friedif Calculator
The Flack and Shmueli Friedif value for a chemical formula, for Cu, Mo and Cr radiation.
CHN Calculator
Elemental analysis percentages from a chemical formula.
CIF Parser
Read a CIF and render its crystallographic data through an HTML or LaTeX template.
New to diffraction?
Two of these are the place to start, and they answer the same question from opposite ends.
The Bragg calculator is the relationship the whole technique rests on: a set of lattice planes a distance d apart reflects a wavelength λ at one particular angle, and nothing else. Put in an angle you measured and it gives you the spacing that caused it.
The HKL calculator goes the other way. Give it a unit cell and a set of Miller indices — the label for one family of planes — and it works out how far apart those planes are, where the reflection will appear, and which other reflections the crystal’s symmetry makes identical to it.
Work one of the examples above through both and the connection becomes concrete: the d the HKL calculator derives from the cell is the same d the Bragg calculator turns into an angle.