2.8 SOLID STATE The quantities and their symbols given here have been selected from more extensive lists of IUPAP [4] and ISO [5.p]. See also the International Tables for Crystallography, Volume A [62].
Name
Symbol
lattice vector fundamental translation vectors for the crystal lattice (circular) reciprocal lattice vector (circular) fundamental translation vectors for the reciprocal lattice unit cell lengths unit cell angles reciprocal unit cell lengths reciprocal unit cell angles fractional coordinates atomic scattering factor
R, R0 a1; a2; a3,
Definition
SI unit
R = n1a1 + n2a2 + n3a3
m m
G R = 2itm
m'
a; b; c
G b1; b2; b,
a, bk
Notes
2 3
2lrĂśjk
a*; b*; c
m
a; b; c c; /3; y
rad, 1
m1
a*; b*; c
*; /3*; y* x; y; z
f
structure factor with indices h,k,l lattice plane spacing Bragg angle order of reflection order parameters, short range long range Burgers vector particle position vector equilibrium position vector of an ion displacement vector of an ion
F(h,k,l)
Debye—Waller factor
B, D
Debye angular wavenumber Debye angular
qD
rad 1, 1
x = X/a
f E/E
F n1= fe2"
1
6
m
d 0 n
1
4 5
1
n) = 2d sin 0
1, rad 1
a
1
s
1
b
m m m
r, R u
u = R — R0
7
m 1
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frequency (1) n1, n2 and n3 are integers, a, b and c are also called the lattice constants. (2) m is an integer. (3) Reciprocal lattice vectors are sometimes defined by a bk = ik (4) X denotes the coordinate of dimension length. (5) Ea and E denote the scattering amplitudes for the atom and the isolated electron, respectively. (6) N is the number of atoms in the unit cell. (7) To distinguish between electron and ion position vectors, lower case and capital letters are used respectively.
The subscript j relates to particle j.
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