
860 Part 4 Functional Materials
Table 4.4-16 Tetragonal, point group 42m (D
2d
) materials, cont.
General Static Dissipation Elastic Piezoelectric Elastooptic
dielectric tensor factor stiffness tensor tensor tensor
Material
g/cm
3
ε
S
11
tan δ
1
c
11
d
14
p
11
Mohs hardness ε
S
33
tan δ
3
c
33
d
36
p
12
κ ⊥ c ε
T
11
c
44
(10
−12
C/N) p
13
κ c ε
T
33
( f (kHz)) c
66
p
31
(W/mK) c
12
p
33
c
13
p
44
(10
9
Pa) p
66
Potassium dihydrogen 2.87 53 [4.420] 0.007 64.8 17.1 –
arsenate, − 18 [4.420] 0.008 48.2 19.1 [4.406] –
KH
2
AsO
4
(KDA) − 53.7 [4.421] (10 GHz) 10.75 –
− 21.0 [4.421] [4.420] 6.63 –
0.77 –
13.6 [4.422] –
0.020 [4.373,374]
Potassium dihydrogen 2.3383 42.5(15) 0.004 71.2(14) 3.5(15) 0.256(18)
phosphate, 2.5 20.0(5) (9.2 GHz) 57(1) 22.4(10) 0.254(19)
KH
2
PO
4
(KDP) 1.34 (⊥c) 43.2(15) [4.423] 12.6(4) [4.401, 402] 0.224(34)
(42
◦
C) 20.8(5) 0.0005 6.2(1) 0.227(8)
1.21 ( c) [4.97, 98] (1 GHz) −5.0(11) 0.200(54)
[4.262] [4.97,98] 14.1(14) [4.7] −0.265(10)
−0.063(6)
(589–633 nm)
[4.409,410]
Rubidium dideuterium 3.333 72
a
1.6 49.3 14.6
arsenate, RbD
2
AsO
4
− 41
ac
[4.369] 2.3 38.6 45.8
c
(RbD
∗
A, RD
∗
A, DRDA) − (1 kHz) 9.48 [4.424]
− [4.369]
c
4.08
−19.3
4.9 [4.424]
Rubidium dideuterium – 3.3(3)
phosphate, RbD
2
PO
4
72
a
52(1)
(RbD
∗
P, RD
∗
P, DRDP) [4.425,426] See [4.427, 428]
c
Rubidium dihydrogen 3.28 54.5
a
2.1 51.0 9.9 0.227
arsenate, RbH
2
AsO
4
− 28.5
a
[4.429] 5.2 [4.429] 39.2 28.5 0.239
(RbDA, RDA) − 10.4 [4.400, 424] 0.200
− 4.31 0.205
−18.9 0.182 [4.430,431]
2.3 [4.424] –
0.023 [4.373,374]
Part 4 4.4