Calcium Fluoride
CaF2
 

Crystal properties

Crystal Type

cubic, CaF2 type structure

 

Transmission Rang:

0.13 ... 12 µm

Density

3.18 g/cm3

Melting Point

1360, 1395 °C

Molecular Weight

78.0768

Thermal Conductivity

9.71 W/(m K)

Specific Heat:

854 J/(kg K)

Thermal Expansion

18.7; 18.85; 24.0 × 10–6 / K

Hardness (Knoop)

158.3

Young’s Modulus

75.8 GPa

Shear Modulu:

33.77 GPa

Bulk Modulus

82.71 GPa

Rupture Modulus

36.5 MPa

Elastic Coefficient:

C11 = 164 
C12 = 53 
C44 = 33.7 GPa

Dielectric Constant

6.76 @ 27 °C

Solubility in Wate:

0.0017 g / 100 g @ 20 °C

Cleavage Planes

(111)

Applicatio:

Spectroscopy, astronomy, lithography 
laser windows for Excimer lasers 
scintillators (CaF2:Eu)

Remarks

deliverable in IR, UV and DUV quality

List of Optical Crystals

Materials

Refractive Index

Transmissio n
Range (mm)

Density
(g/cm³)

Thermal Expansion  
Coefficient (10-6/K) 

BK7 glass

1.5164 (588 nm)

0.330 – 2.1

2.51

7.5 

SF11 glass

1.78472 (588 nm)

0.370 – 2.5

4.74

6.8 

F2 glass

1.62004 (588 nm)

0.420 – 2.0

3.61

8.2 

Fused Silica

1.4858 (308 nm)

0.185 – 2.5

2.20

0.55 

CaF2

1.399  (5.0 mm)

 0.170 – 7.8

 3.18

 18.85 

BaF2

 1.460 (3.0 um)

 0.15 – 12.0

 4.88

 18.4 

Sapphire

1.755 (1.0mm)

0.180 – 4.5

3.98

8.4 

Silicon

3.4179 (10mm)

 1.200 – 7.0

 2.33

 4.15 

Ge

4.003 (10 mm)

 1.900 – 16

 5.33

 6.1 

ZnSe

2.40  (10 mm)

0.630 – 18

5.27

7.8 

ZnS

2.2 (10mm)

0.380 –14

4.09

6.5 

LiF

1.39 (500 nm)

 0.150 – 5.2

 2.64

37 

KBr

1.526 (10 mm)

 0.280 – 22

 2.75

43 

 MgF2

no =  1.3836  ne = 1.3957 (405 nm)

0.130 – 7.0

7.37

a: 13.7         b: 8.48 

YVO4

no = 1.9500  ne = 2.1554 (1.3 mm)

0.400 – 5.0

4.22

a: 4.46       b: 11.37 

Calcite

no =  1.6557  ne = 1.4852 (633 nm)

0.210 – 2.3

2.75

a: 24.39        b: 5.68 

Quartz

no =  1.5427  ne = 1.5518 (633 nm)

0.200 – 2.3

2.65

7.07 

α-BBO

no =  1.6749  n= 1.5555 (532 nm)

0.190 – 3.5

3.85

a: 4.0           c: 36 

LiNbO3

no =  2.2863  ne = 2.2027 (633 nm)

0.370 – 4.5

4.64

a: 16.7          c: 2.0