TLS refinement is generally valid at any resolution; at low resolution, it may be best to make each chain a single group, instead of trying to split them into smaller pieces. However, it is best to wait until near the end of refinement to add TLS; until then you should refine with isotropic ADPs only.
What is anisotropic B factor?
An anisotropic scale factor is a multiplicative factor like the overall B-factor. Like the overall B-factor, its value varies with resolution. But, unlike the overall B-factor, its value also varies with direction.
What is goodness of fit in crystallography?
Goodness of fit refers to the least-squares refinement and not to the crystal. You can refine the X-ray diffraction (single crystal or powder) data with a structure model and get these quality factors.
What is protein refinement?
Protein model refinement is the last step applied to improve the quality of a predicted protein model. Currently, the most successful refinement methods rely on extensive conformational sampling and thus take hours or days to refine even a single protein model.
What is R1 in crystallography?
R1, often called the R-value, is the agreement between the calculated and observed models. The formula for this value is R1= |S |Fo|-|Fc| | / |S |Fo| |. Ideal solutions would have R-values of 0, however, due to random errors, this is never achieved.
What is a good B factor crystallography?
A good model should show average devations from expected values of no more than 0.2 angstroms in bond lengths and 4 degrees in bond angles. Another result of crystallographic structure determination is a number called a B-factor or temperature factor for each atom.
What is Biso factor?
Negative value of Biso means that there are some other factors influencing intensities – preferred orientation/disorder at different sites, which are not taken into account in your current model. Strongly negative values of Biso, less than -0.3 means that something is really wrong.
What is GooF olex2?
GooF is the goodness of fit of a structure and should converge towards 1 at the end of the refinement.
