Temperature value: Difference between revisions

In [[X-ray crystallography|crystallography]], '''uncertainty''' in the positions of atoms increases with '''disorder''' in the protein crystal. Disorder may have two components, static and dynamic. [[Resolution]] represents the average uncertainty for all atoms. In contrast, the ''temperature value'' (also called ''temperature factor'' or ''B factor'') quantitates the local uncertainty for each atom. At typical resolutions for protein crystals (where ''occupancy'' cannot be distinguished from ''B value''), a high temperature factor reflects a low [[Electron density map|empirical electron density]] for the atom, and ''vice versa''. The temperature value is recorded in the [[atomic coordinate file]]. In the [[PDB_file#PDB_Data_Format|PDB file format]], it is the last numeric value (columns 61-66) in each ATOM and HETATM record. [[#Coloring By Temperature|Coloring by temperature]] is a common way to visualize the uncertainty for each atom.