Optical constants
Refractive index of CaCO3 - Calcite (o) (CRYSTRAN)
CaCO3 - Calcite (o): n,k 0.2–2.1 µm
- Data
- tabulated n + tabulated k
- Range
- 0.2–2.1 µm
- Points
- 12
- Optical axis
- o
- State
- crystalline
- Licence
- CC0-1.0
Uniaxial crystal, axes: oe
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 1.65915
- Extinction coefficient k
- 0
- Permittivity ε1
- 2.75278
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0792308 µm⁻¹
- Group index ng
- 1.70571
- Group velocity dispersion
- — fs²/mm
- Dispersion parameter D
- — ps/(nm·km)
- Photon energy
- 2.11001 eV
ε = (n + ik)², α = 4πk/λ, ng = n − λ dn/dλ, GVD = λ³/(2πc²) d²n/dλ², D = −(λ/c) d²n/dλ². Group-velocity dispersion is given for formula data only.
Use it in Lightsmith
Load this data in Python, simulate in one more line
pip install lightsmith
import lightsmith as ls
# CaCO3 - Calcite (o) (CRYSTRAN): CaCO3 - Calcite (o)
crystran_caco3_o = ls.fetch_refractiveindex("specs", "CRYSTRAN-optical", "CaCO3-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(crystran_caco3_o.range_nm) # (200, 2100) nm
eps = crystran_caco3_o.eps([633]) # complex permittivityDownloads the original record once (pinned to the imported snapshot) and caches it.
import json, urllib.request
import lightsmith as ls
url = "https://materials.lightsmith.dev/v1/datasets/ds_1b03801a25b2/lightsmith"
crystran_caco3_o = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(crystran_caco3_o.source) # citation and provenance travel with the dataAny dataset here, as the library's Tabulated material (crystran-caco3-o/crystran).
# ... load crystran_caco3_o as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=crystran_caco3_o)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=1000, num=81),
)
res = ls.solve(sim) # exact Mie for a sphere
print(res.q_ext) # extinction efficiency at each wavelengthSame spec runs with DDA, FDTD, BEM or T-matrix: ls.compare(sim, ["mie", "dda"]).
Lightsmith is open source (MIT): Mie, T-matrix, BEM, DDA, FDTD, RCWA, TMM, mode solvers and inverse design behind one spec, on CPU or GPU. GitHub.
Comments and conditions
Conditions
- direction
- o
Properties
- density
- value: 2710
- thermal dispersion
- type: constant, value: 3e-06, direction: para, wavelength: 0.5; type: constant, value: 1.3e-05, direction: perp, wavelength: 0.5
- thermal expansion
- value: 25e-06, direction: para, temperature: 273; value: -5.8e-06, direction: perp, temperature: 273
- hardness
- type: Knoop, value: 1.52e9; type: Mohs, value: 3
- melting point
- value: 1098
- thermal conductivity
- value: 5.526, direction: para, temperature: 273; value: 5.526, direction: perp, temperature: 273
- youngs modulus
- value: 88.19e9, direction: para; value: 72.35e9, direction: perp
- solubility
- value: 0.014
Thermo-optic coefficient
- dn/dT = 3.00e-06 K⁻¹ at 500 nm (para)
- dn/dT = 1.30e-05 K⁻¹ at 500 nm (perp)
References
See also Crystran CaCO3 online data sheet
Cite
Crystran Ltd. The Crystran handbook of infra-red and ultra-violet optical materials (5th edition, 2023); See also Crystran CaCO3 online data sheet; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
Computed on 12 wavelengths, the same grid as the API and the library| λ (µm) | n | k |
|---|---|---|
| 0.2 | 1.9028 | 3.350000e-05 |
| 0.3 | 1.7196 | 1.960000e-07 |
| 0.41 | 1.6801 | 0 |
| 0.51 | 1.6653 | 0 |
| 0.64 | 1.655 | 0 |
| 0.71 | 1.6521 | 0 |
| 0.8 | 1.6487 | 0 |
| 0.91 | 1.6458 | 0 |
| 1.04 | 1.6428 | 0 |
| 1.5 | 1.6346 | 1.800000e-06 |
| 1.91 | 1.627 | 3.580000e-06 |
| 2.1 | 1.622 | 3.560000e-06 |
Optical transmission calculator
Free-standing sample in vacuum, normal incidence- Transmittance T
- —
- Reflectance R
- —
Fresnel reflection calculator
- Rp
- —
- Rs
- —
- R = (Rp+Rs)/2
- —
- Phase φp
- —
- Phase φs
- —
- Brewster angle θB
- —
- Critical angle θC
- —
Calcite, or Iceland Spar, is a strongly birefringent material and is used for polarisers and retardation plates. Calcite is often mined naturally. Crystran Ltd has a stock of small calcite "rhombs" of good clear optical quality. Calcite cuts and polishes well.
CLEAVEAGE PLANE:
There can be confusion in the definition of the cleavage plane in calcite. Conventionally this has always been referred to as {10-11} but recent papers on AFM studies use {10-14}. Calcite cleaves between the bonds of the CO3 groups (in the CO3 layer). The CO3 group are offset relative to each other and inclined to the c axis giving 3 cleavage directions defining a rhomb. Following the {10-11} nomenclature the unit cell requires ¼ the length of the c axis as measured from XRD (on a dimension 4 times longer). The correct Miller indices are {10-14} but the conventional {10-11} is often used in order not to confuse and for easier comparison. (1)
REFERENCES:
1. Private Communication. J.A.Elliott. Dept. Materials Science, University of Cambridge. 2011
2. Crystallography - LINK to: Practical Crystal Measurement. A.E.H.Tutton, Vol2, page 1329
3. Linear Thermal Expansion of Calcite - Link to: Mineral Society of America, Linear Thermal Expansion of Calcite.
WEBLINKS:
http://webmineral.com/data/Calcite.shtml - Has further information regarding Calcite.
Optical data are for ordinary ray (o).