氟化镁 Magnesium Fluoride (MgF2)
Crystallographic
Syngony |
Tetragonal |
Symmetry Class |
4/mmm |
Lattice Constants |
a = 4.64 Å c = 3.06 |
Cleavability |
(100),(110) perfect |
Thermal
Refractive Index at ne |
1.3786 |
Refractive Index at nF' - nC' |
1.3904 |
Refractive Index at n10.6 |
0.0034 |
Refractive Index at n8.0 - n12.5 |
0.0110 |
Thermal Coefficient of Refractive Index at 3.39 microns for ±60 ℃ |
βo = (0.15 ... 0.10) x 10-5 βe = (0.15 ... 0.10) x 10-5 |
Transmission Range, microns |
0.13 - 7.0 |
Thermal
Thermal Linear Expansion, ℃-1 for ±60 ℃ |
|
⊥ to c-axis |
(6.23 ... 9.25) x 10-6 |
|| to c-axis |
(10.86 ... 14.54) x 10-6 |
Specific Heat Capacity, J/(kg * ℃) |
0.9200 x 103 |
Melting Point, ℃ |
1255 |
Mechanical
Density, g/cm3 at 20 ℃ |
3.18 |
Mohs Hardness |
6 |
Vickers Microhardness, Pa |
|
⊥ to c-axis |
441 x 107 |
|| to c-axis |
289 x 107 |
Constants of Elastic Compliance, Pa-1 |
S11 = 12.45 x 10-12 S12 = -7.16 x 10-12 S13 = -1.66 x 10-12 S33 = 5.94 x 10-12 S44 = 17.54 x 10-12 S66 = 10.53 x 10-12 |
Young Modulus (E), Pa |
|
⊥ to c-axis |
16.91 x 1010 |
|| to c-axis |
7.97 x 1010 |
Shear Modulus (G), Pa |
|
⊥ to c-axis |
5.71 x 1010 |
|| to c-axis |
9.52 x 1010 |
Poisson Ratio |
|
|| to c-axis |
0.577 |
Chemical
Molecular Weight |
62.32 |
Solubility |
|
in water, gram/100 cm3 |
0.0076 |
in acids |
soluble |
Ref. Index vs. Wavelength λ
Wavelength, Microns |
Refractive Index no |
Refractive Index ne |
0.2 |
1.4231 |
1.4367 |
0.5 |
1.3797 |
1.3916 |
1.0 |
1.3736 |
1.3852 |
2.0 |
1.3686 |
1.3797 |
3.0 |
1.3618 |
1.3724 |
4.0 |
1.3525 |
1.3622 |
5.0 |
1.3400 |
1.3487 |
6.0 |
1.3242 |
1.3315 |
7.0 |
1.3044 |
1.3101 |
Internal Transmittance τ i (λ) vs. Wavelength λ
Wavelength, Microns |
Internal Transmittance |
0.2 |
0.95 |
0.5 |
0.97 |
1.0 |
0.97 |
3.0 |
0.97 |
5.0 |
0.97 |
6.0 |
0.91 |
7.0 |
0.54 |
8.0 |
0.12 |
Custom sizes and specifications are available on request.