
610 Part 4 Functional Materials
D. Electromagnetic and Optical Properties
Table 4.1-36.
Table 4.1-36 Dielectric constant ε and refractive index n of boron compounds
Crystal Temperature (K) ε(0) ε(∞) n at λ(nm) Remarks
Boron nitride, cubic BN
cub
300 7.1 2.097 712.5 IR reflectivity
Boron nitride, hexagonal BN
hex
300 5.09 4.10 2.13 Parallel to c axis, IR reflectivity
7.04 4.95 1.65 Perpendicular to c axis, IR reflectivity
Boron phosphide BP 300 11 7.8 Schottky barrier reflectance
RT 3.34 (5) 454.5 Brewster angle method
3.34 (5) 458
3.32 (5) 488
3.30 (5) 496
3.26 (5) 514.5
3.00 (5) 632.8
4.1.2.2 Aluminium Compounds
A. Crystal Structure, Mechanical and Thermal Properties
Tables 4.1-37 – 4.1-44.
Table 4.1-37 Crystal structures of aluminium compounds
Crystal Space group Crystal system Structure type Remarks Figure
Aluminium nitride AlN I C
4
6v
P6
3
mc hex Wurtzite At normal pressure Fig. 4.1-3
AlN II
O
5
h
Fm3m fcc NaCl structure At 21 GPa (shock
compression)
Aluminium phosphide AlP I T
2
d
F
4
3m
fcc Zinc blende At normal pressure Fig. 4.1-2
AlP II O
5
h
Fm3m fcc NaCl structure High-pressure phase
Aluminium arsenide AlAs T
2
d
F
4
3m
fcc Zinc blende Transition to NiAs structure Fig. 4.1-2
at high pressure
Aluminium antimonide AlSb I T
2
d
F
4
3m
fcc Zinc blende At normal pressure Fig. 4.1-2
AlSb II Cmcm Orthorhombic At high pressure
Table 4.1-38 Lattice parameters of aluminium compounds
Crystal Lattice parameters (nm) Temperature Remarks
Aluminium nitride AlN a = 0.31111 300 K X-ray diffraction on ultrafine powder
c =0.49788
Aluminium phosphide AlP a = 0.54635 (4) 25
◦
C Epitaxial film on GaP
Aluminium arsenide AlAs a = 0.566139 291 K High-resolution X-ray diffraction
Aluminium antimonide AlSb a = 0.61355 (1) 291.15 K Powder, X-ray measurement
Part 4 1.2