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There is another good reason why you should run TLSANL to produce the PDB file for deposition after doing a TLS refinement in REFMAC: the ANISOU cards it produces should in principle be unique for a given structure, but the TLS matrices and additive isotropic B's are not! You can add a constant value to these B values for all atoms in the same TLS group and subtract it from the diagonal elements of the T tensor for that group, and the fit is unchanged. In other words REFMAC refines one parameter too many per TLS group, and if it were able to do a full matrix refinement this would cause it to blow up with a singular matrix (Garib: please do not interpret this as a criticism, the REFMAC approach is a good practical solution to a tricky problem and we make good use of the TLS refinement in REFMAC).
Possibly some future version of a refinement program will apply TLS restraints rather than constraints, this could be programmed in a way that would refine the Uij values directly and so avoid this problem. The deposition of restrained Uij values would then be on a par with the deposition of restrained atom coordinates (which we do all the time).
George -- Prof. George M. Sheldrick FRS Dept. Structural Chemistry, University of Goettingen, Tammannstr. 4, D37077 Goettingen, Germany Tel. +49-551-39-3021 or -3068 Fax. +49-551-39-2582
