Debye-Waller factor - Revision history

Christoph at 06:42, 15 October 2021

2021-10-15T06:42:42Z

Christoph at 23:41, 27 September 2006

2006-09-27T23:41:14Z

Christoph at 22:51, 27 September 2006

2006-09-27T22:51:06Z

Christoph at 22:50, 27 September 2006

2006-09-27T22:50:17Z

Christoph at 22:45, 27 September 2006

2006-09-27T22:45:01Z

New page

The '''Debye-Waller factor''', also known as the '''B-factor''' or the '''temperature factor''' describes the decrease in scattering intensity (either from x-ray or neutron scattering) due to the thermal motion of the atoms, or due to crystal disorder. The thermal motion, or disorder, in some sense reduces the validity of the Laue diffraction condition which is based on fixed atoms.


I = I_0 * exp(-1/3 * |G|^2 * u^2)

I is the weakened intensity and I0 the source intensity. G is a [[Reciprocal lattice|reciprocal lattice vector]] and u the thermally enhanced oscillation amplitude of the atoms.

Higher orders of Bragg reflection are weakened more.

== Restrictions ==
Normally, the following restrictions apply to the anisotropic B-factor tensor
{| align="center" style="border: 1px solid #999; background-color:#FFFFFF"
|--bgcolor="#eeeeee"
| [http://en.wikipedia.org/wiki/Triclinic Triclinic]
|| none
|-----
| [http://en.wikipedia.org/wiki/Monoclinic Monoclinic]
|| B13 = B23 = 0 when β = α = 90° 
B12 = B23 = 0 when γ = α = 90° 
B12 = B13 = 0 when γ = β = 90°
|--bgcolor="#eeeeee"
| [http://en.wikipedia.org/wiki/Orthorhombic Orthorhombic]
|| B12 = B13 = B23 = 0
|-----
| [http://en.wikipedia.org/wiki/Tetragonal Tetragonal]
|| B11 = B22 and B12 = B13 = B23 = 0
|--bgcolor="#eeeeee"
| [http://en.wikipedia.org/wiki/Rhombohedral Rhombohedral]
|| B11 = B22 = B33 and B12 = B13 = B23
|-----
| [http://en.wikipedia.org/wiki/Hexagonal_%28crystal_system%29 Hexagonal]
|| B11 = B22 and B13 = B23 = 0
|--bgcolor="#eeeeee"
| [http://en.wikipedia.org/wiki/Cubic_crystal_system Cubic]
|| B11 = B22 = B33 and B12 = B13 = B23 = 0
|}

== External links ==
* [http://en.wikipedia.org/wiki/Debye-Waller_factor Wikipedia article on '''Debye-Waller factor''']

[[Category:Academic Research]]
[[Category:Crystallography]]

@@ Line 4: / Line 4: @@
   I = I_0 * exp(-1/3 * |G|^2 * u^2)
-I is the weakened intensity and I<sub>0</sub> the source intensity. G is a [http://en.wikipedia.org/wiki/Reciprocal_lattice reciprocal lattice vector] and u the thermally enhanced oscillation amplitude of the atoms.
+''I'' is the weakened intensity and ''I<sub>0</sub>'' the source intensity. ''G'' is a [http://en.wikipedia.org/wiki/Reciprocal_lattice reciprocal lattice vector] and ''u'' the thermally enhanced oscillation amplitude of the atoms.
 Higher orders of Bragg reflection are weakened more.

@@ Line 4: / Line 4: @@
   I = I_0 * exp(-1/3 * |G|^2 * u^2)
-I is the weakened intensity and I<sub>0</sub> the source intensity. G is a [[Reciprocal lattice|reciprocal lattice vector]] and u the thermally enhanced oscillation amplitude of the atoms.
+I is the weakened intensity and I<sub>0</sub> the source intensity. G is a [http://en.wikipedia.org/wiki/Reciprocal_lattice reciprocal lattice vector] and u the thermally enhanced oscillation amplitude of the atoms.
 Higher orders of Bragg reflection are weakened more.

← Older revision		Revision as of 22:50, 27 September 2006
Line 39:		Line 39:
	* [http://en.wikipedia.org/wiki/Debye-Waller_factor Wikipedia article on '''Debye-Waller factor''']		* [http://en.wikipedia.org/wiki/Debye-Waller_factor Wikipedia article on '''Debye-Waller factor''']

−	~~[[Category:Academic Research]]~~
	[[Category:Crystallography]]		[[Category:Crystallography]]

@@ Line 9: / Line 9: @@
 == Restrictions ==
-Normally, the following restrictions apply to the anisotropic B-factor tensor
+Normally, the following restrictions apply to the [http://en.wikipedia.org/wiki/Anisotropic anisotropic] B-factor tensor
 {| align="center" style="border: 1px solid #999; background-color:#FFFFFF"
 |--bgcolor="#eeeeee"
@@ Line 38: / Line 38: @@
 == External links ==
 * [http://en.wikipedia.org/wiki/Debye-Waller_factor Wikipedia article on '''Debye-Waller factor''']
 [[Category:Crystallography]]