An interesting discussion of the development of the Debye-Waller
correction can be found in the IUCr publication, "Fifty Years of X-
Ray Diffraction," edited by P.P. Ewald (unfortunately, it's no longer
in print). It seems that Debye was the first scientist to tackle "a
problem which appeared to others hopelessly complicated at the time:
the influence of the temperature motion of the atoms on the
diffraction of X-rays (p. 79 of aforementioned publication)."
Interestingly, his original formulation of the correction included
the constant M, "which can be expressed by means of the elastic
properties of the crystal or their combination, the 'Debye
Temperature', which occurs in the theory of the specific heat (same
reference)." The text goes on to mention that Ivar Waller
demonstrated in 1923 that Debye's expression for M was wrong by a
factor of two. No mention is given in "Fifty Years" of a "B factor"
but it sounds as though Waller decided to use a different
nomenclature in his paper from 1927 to avoid confusion.
Too bad that "Fifty Years" is no longer in print, though used copies
can be purchased from various on-line booksellers. It provides a very
enlightening and easily readable history of the early days in the
field, and the interchange of scientists and ideas across the
Atlantic Ocean.
Diana
On Jan 24, 2007, at 11:14 AM, Santarsiero, Bernard D. wrote:
> It looks like the earliest reference to the Debye-Waller factor is
> from
> Debye's paper:
>
> Uber den Einfluss der Warmebewegung uf die Interferenzerscheinungen
> beiu
> Rontgenstrahlen, Verhandl. deut. phyik. Ges., 15, 678-689 (1913),
>
> and the succeeding paper Verhandl. deut. phyik, Ges., 15, 738-752
> (1913),
>
> and Waller:
>
> Die Einwirkung der Warmbewegung der Kristllatome auf Intersitat,
> Lage, and
> Scharfe der Rontgenspektrallinein, Ann. Physik, 83, 153-183 (1927).
>
> Interestingly, beta was used for the anisotropic Gaussian form of the
> isotropic Gaussian B-factor.
>
> Bernie
>
>
>
> On Wed, January 24, 2007 9:05 am, Roberto Steiner wrote:
>> Hi Rajesh,
>>
>> I also wondered about that.
>> Not having been able to find a good explanation in the literature
>> I thought of it as reducing factor of the *B*ragg peaks. Mhhhh???
>>
>> Then I stopped thinking about it (I now try to call them ADPs)
>>
>>
>> Roberto
>>
>> On 24 Jan 2007, at 12:42, Rajesh Kumar Singh wrote:
>>
>>> May be too trivial, I was just wondering
>>> what "B" stands for in the term "B-factor".
>>>
>>> Thanks
>>>
>>> Rajesh
>>>
>>> --
>>> Rajesh Kumar Singh
>>> Institut fur Biochemie
>>> Universitat Greifswald
>>> Felix-Hausdorff-Str. 4
>>> D-17489 Greifswald
>>> Germany
>>>
>>> E.Mail: [log in to unmask]
>>> Phone: +49-3834- 86 4392
>>
>> ---
>> Dr. Roberto Steiner
>> Randall Division of Cell and Molecular Biophysics
>> New Hunt's House
>> King's College London
>> Guy's Campus
>> London, SE1 1UL
>> Phone +44 (0)20-7848-8216
>> Fax +44 (0)20-7848-6435
>> e-mail [log in to unmask]
>>
* * * * * * * * * * * * * * * * * * * * * * * * * * * *
Diana R. Tomchick
Associate Professor
University of Texas Southwestern Medical Center
Department of Biochemistry
5323 Harry Hines Blvd.
Rm. ND10.214B
Dallas, TX 75390-8816, U.S.A.
Email: [log in to unmask]
214-645-6383 (phone)
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