Transmission Range

0.18 ... 3.6 µm

Refractive Index

n^o= 1.6775, n^e= 1.6899 @ 185 nm 
n^o= 1.5709, n^e= 1.5809 @ 325 nm 
n^o= 1.5482, n^e= 1.5575 @ 508 nm 
n^o= 1.5423, n^e= 1.5513 @ 644 nm 
n^o= 1.5201, n^e= 1.5282 @ 2.05 µm 
n^o= 1.4995, n^e= 1.5070 @ 3.00 µm

dn / dT

–6.5 ×10^–7 / K || Y, –5.5 ×10^–7 / K _|_ Y

Density

2.648 g/cm³

Melting Point

1700 °C

Molecular Weight

60.08

Thermal Conductivity

1.4 W/(m K)

Specific Heat

787 J/(kg K) @ 25 °C

Thermal Expansion

5 ×10^–7

Hardness (Knoop)

461 @ 200 g, 741 @ 500 g indenter load

Young's Modulus

76.5 GPa _|_ Y , 97.2 GPa || Y

Shear Modulus

36.4 GPa / 57,13 GPa

Bulk Modulus

98.98 GPa

Elastic Coefficient

C¹¹ = 86.75 / C¹² = 6.87 / C¹³ = 11.3 /
C³³ = 106.8 / C⁴⁴ = 57.86 GPa

Dielectric Constant

3.9 / 4.34

Solubility in Water

insoluble

Crystal Structure

single crystal

Cleavage Planes

none

AT cut = + 35^o from Z towards Y

BT cut = - 49^o from Z towards Y

CT cut = + 38^o from Z towards Y

DT cut = - 52^o from Z towards ^Y

ET cut = - 66^o from Z towards Y

FT cut = - 57^o from Z towards Y