A version of SHELXL adapted to multiple CPUs by Kay Diederichs has been available from the SHELX download site for several years (in the mp subdirectory). The precompiled 4-thread version works fine on dual-core and quad-core Linux PCs and really does run two or four times faster. For other systems (e.g. an IntelMac Octacore running MacOSX) one has to recompile.
I am not convinced of the need to produce multithreaded versions of SHELXD and SHELXE because it is a good idea to run these programs several times in parallel anyway, e.g. with different resolution cutoffs (heavy atom location with SHELXD) or different solvent content (density modification with SHELXE). Several GUIs already do this automatically. Molecular replacement programs (and Refmac) would be good candidates for exploiting multiple CPU machines! 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
