P

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

parent clamping approximation
partial symmetry
Patterson methods
Patterson vector
Pearson symbol
phase of a modulation
phase problem
phase transition
piezoelectricity
pleochroism
point configuration
point group
point space
point symmetry
polar lattice
Polyamorphism
polymorphism
polytypism
powder
preferred orientation
primary extinction
primitive basis
primitive cell
priority rule
pseudo symmetry
pyroelectricity