On a more prosaic note, how about "bewegung?" See Waller, I. (1927) Ann. Physik. 88:153.
Joe Becker -----Original Message----- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Gerard DVD Kleywegt Sent: Wednesday, January 24, 2007 10:10 AM To: [email protected] Subject: Re: [ccp4bb] "B" in B-factor > May be too trivial, I was just wondering > what "B" stands for in the term "B-factor". i don't really know, but i do have some wild theories, none of which are necessarily based in fact: - the B-factor is also called the Debye-Waller factor. now, someone assumed that peter debye was french (instead of dutch) and that his name should be written "de Bye"; hence the B as the "first" letter in his name (something similar happened to monsieur luzzati whose oft-abused 1952 paper is headed "Par V. Luzzati" which probably led some people to believe he was swedish and that "Par" was his first name. once "P.V. Luzzati" made it into the x-plor manual (e.g., http://nmr.cit.nih.gov/xplor-nih/xplorMan/node484.html) mis-citations of this kind mushroomed, mostly by people who couldn't read the original paper because it was in french, in which language "par" means (written) "by") - there was a lot of buzz when the concept was first introduced which led to associations with bees; hence "bee-factor" or, shortened, "B-factor" - they wanted to call it "A-factor" first, but realised that the A could be mistaken for the indefinite article which they definitively didn't want. i mean, how cool is "a factor" ? hence the B-factor - the name follows the same path as that of the programming language "C" (which was simply the third version of a draft, where the earlier versions had been called "A" and "B"), but they got it right in only two tries. the first draft ("A-factor") was correct down to a factor of pi. once the bug had been removed, the second version (that we still use today) was called the "B-factor" - around 1920, there was a heated debate as to whether or not a thermal factor was really necessary or merely a modernistic luxury. this discussion was held in the carrier-pigeon-based predecessor of the ccp4 bulletin board (little-known fact: a lot of carrier pigeons had been bred by the british for communication duties during world war I and they found good jobs after the war in operating various bulletin boards) where a classically trained crystallographer semi-facetiously titled the thread "thermal factors - to be or not to be ?". When the debate subsided and the need for a new factor was agreed upon, it was only logical to call it the "B-factor" (actually, it was first called the "2B-factor" which differed from the modern B-factor by a factor of 2, but this was deemed too confusing) - the name "B-factor" was first coined by george sheldrick. by coincidence, he had just exhausted all the possible Fortran variable names starting with A (A, A1, A2, A3, ...) when he was about to implement isotropic thermal factor refinement in SHELX53. so the logical (and bold, if painful) step george took was to make this parameter the first in a (for him) whole new universe of Fortran variable names: B - it was invented by sacha baron cohen's great-grandfather. indeed, "B-factor" is an anagram of "Borat FC" ("fc" meaning "football club") i'm sure other ccp4bb-ers can come up with better explanations --dvd ****************************************************************** Gerard J. Kleywegt [Research Fellow of the Royal Swedish Academy of Sciences] Dept. of Cell & Molecular Biology University of Uppsala Biomedical Centre Box 596 SE-751 24 Uppsala SWEDEN http://xray.bmc.uu.se/gerard/ mailto:[EMAIL PROTECTED] ****************************************************************** The opinions in this message are fictional. Any similarity to actual opinions, living or dead, is purely coincidental. ****************************************************************** ------------------------------------------------------------------------------ Notice: This e-mail message, together with any attachments, contains information of Merck & Co., Inc. (One Merck Drive, Whitehouse Station, New Jersey, USA 08889), and/or its affiliates (which may be known outside the United States as Merck Frosst, Merck Sharp & Dohme or MSD and in Japan, as Banyu - direct contact information for affiliates is available at http://www.merck.com/contact/contacts.html) that may be confidential, proprietary copyrighted and/or legally privileged. It is intended solely for the use of the individual or entity named on this message. If you are not the intended recipient, and have received this message in error, please notify us immediately by reply e-mail and then delete it from your system. ------------------------------------------------------------------------------
