
Home > Crystallographic Web Applets Following links from my tutorial web site to Amazon.com allows you to find best new and used prices on crystallography books and helps to support this web site. See also my recommendations. 

A new resolution dependent extension to the basic Matthews Coefficient, introduced by Brian Matthews in the early 70's. Published in Protein Science 12:18651871 (2003) 

Calualtion of elbow angle by the standardized Stanfield method. Needs 2 PDB files, preferrably Kabatnumbered. Published in J. Mol. Biology, 357(5):15661574 (2006). 


A old time favorite. Hammer in a valid space group, and get back transformation matrices, symbolic operators, reciprocal space unit cell, and more.... 

This is useful if you have a model railroad and some legacy DCC decoders that do not have direct long address entry of 4digit decoder addresses. It calculates the register representation (bytes) for CV 17 and CV 18 for the extended 4digit address. 

A predictive tool that computes the crystallization success probabilities for a given protein pI based on the empirical pH distribution in the PDB. The pI is generally not the most likely pH for a protein to crystallize! Published in Bioinformatics 20(14): 21712174 (2004) 

A little calculator that returns the nine CromerMann coefficients, and a corresponding scattering factor curve for a given Bfactor. Also computes the mean displacement equivalent for the given Bfactor. See tutorial page for associated exercises. 

Calculates the structure factors and a 1d diffraction pattern for a onedimensional structure with two atoms in the asymmetric unit. Atom positions, atom type, cell dimension, resolution, Xray wavelength and use of anomalous scattering factors can be selected. See tutorial page for associated exercises. 

From 1d structure factors (calculated from program above) this applet generates a Forurier map and a Patterson map. Effects of grid spacing, resolution, and Fourier truncation effects can be investigated. See tutorial page for associated exercises. 

ANOMALOUS DISPERSION RATIOS, WAVELENGTHENERGY 
Very useful tool for MAD experiments, estimating the anomalous (Bijvoet) and dispersive rations at 4 selectable wavelength and a fixed anode around an absorption edge, depending on protein size and number of anomalous scatterers. Also has a wavelength<>energy converter. See tutorial for associated exercises. 

Simple calculator for dspacing from cell constants for any given hkl plane. Also calculates number of total and unique reflections for a given resolution cutoff. 

Molecular weight, F(000), residue statistics, isoelectric point, and PDB SEQRES residue from sequence. 

Refines cell constants for uniaxial or higher systems using internal standards for different diffraction techniques, wavelengths and standard materials. Please reference XLAT  Least Squares Refinement of Cell Constants, B.Rupp, Scripta Metall. 22, I (1988) when using the program in published work. 
