Optical constants

Refractive index of LiCl (Lithium chloride)

Li 1976: n 0.17–16 µm

Data: formula 1
Range: 0.17–16 µm
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.66208
Extinction coefficient k: 0

Permittivity ε₁: 2.7625
Permittivity ε₂: 0

Absorption coefficient α: 0 cm⁻¹
Penetration depth δ = λ/(2πk): — nm

Abbe number V_d: 209.69
Chromatic dispersion dn/dλ: -0.016266 µm⁻¹

Group index n_g: 1.67163
Group velocity dispersion: 28.6318 fs²/mm

Dispersion parameter D: -156.202 ps/(nm·km)
Photon energy: 2.11001 eV

ε = (n + ik)², α = 4πk/λ, n_g = 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

# LiCl (Lithium chloride): Li 1976: n 0.17–16 µm
licl = ls.fetch_refractiveindex("main", "LiCl", "Li", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(licl.range_nm)  # (170, 16000) nm
eps = licl.eps([633])  # complex permittivity

Downloads 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_7dd60ee24a7d/lightsmith"
licl = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(licl.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (licl/li-1976).

# ... load licl as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=licl)],
    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 wavelength

Same spec runs with DDA, FDTD, BEM or T-matrix: ls.compare(sim, ["mie", "dda"]).

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_7dd60ee24a7d/lightsmith?model=drude_lorentz"
licl_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))

A dispersive Drude–Lorentz model for time-domain solvers.

Materials guide Open a sphere of it in Studio Quick start Ask the community

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.

Dispersion formula

Sellmeier (formula 1), λ in µm

n^{2} - 1 = 1.51 + \frac{0.24 λ^{2}}{λ^{2} - {0.137}^{2}} + \frac{9.11 λ^{2}}{λ^{2} - {49.26}^{2}}

Valid from 0.17 to 16.0 µm.

Coefficients as stored

C_i	Value
C1	1.51
C2	0.24
C3	0.137
C4	9.11
C5	49.26

Comments and conditions

297 K (24 °C).

References

H. H. Li. Refractive index of alkali halides and its wavelength and temperature derivatives. J. Phys. Chem. Ref. Data 5, 329-528 (1976) and references therein.
* Sellmeier formula is derived by critical analysis of experimental data from several sources.

doi:10.1063/1.555536 Refractive index of alkali halides and its wavelength and temperature derivatives, Journal of Physical and Chemical Reference Data (1976)

Cite

H. H. Li. Refractive index of alkali halides and its wavelength and temperature derivatives. Journal of Physical and Chemical Reference Data, 5, 329-528 (1976), doi:10.1063/1.555536; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

Computed on 400 wavelengths, the same grid as the API and the library

CSV comma separated TXT tab separated YAML n, k Full database record original YAML All quantities CSV JSON metadata

LiCl (Lithium chloride), Li 1976: n 0.17–16 µm: n and k versus wavelength
λ (µm)	n
0.17	1.787323
0.171947	1.779634
0.173917	1.772663
0.175909	1.766314
0.177924	1.76051
0.179962	1.755184
0.182024	1.750281
0.184109	1.745753
0.186218	1.74156
0.188351	1.737667
0.190509	1.734044
0.192691	1.730664
0.194898	1.727504
0.197131	1.724545
0.199389	1.721769
0.201673	1.719159
0.203983	1.716702
0.206319	1.714385
0.208683	1.712198
0.211073	1.71013
0.213491	1.708172
0.215937	1.706316
0.21841	1.704554
0.220912	1.702881
0.223443	1.70129
0.226002	1.699775
0.228591	1.698331
0.231209	1.696955
0.233858	1.695641
0.236537	1.694386
0.239246	1.693186
0.241987	1.692038
0.244759	1.690939
0.247563	1.689886
0.250398	1.688876
0.253267	1.687908
0.256168	1.686978
0.259102	1.686086
0.26207	1.685228
0.265072	1.684403
0.268109	1.683609
0.27118	1.682846
0.274286	1.68211
0.277428	1.681402
0.280606	1.680719
0.28382	1.680061
0.287071	1.679426
0.29036	1.678813
0.293686	1.678222
0.29705	1.67765
0.300453	1.677099
0.303894	1.676565
0.307375	1.67605
0.310896	1.675551
0.314458	1.675069
0.31806	1.674602
0.321703	1.67415
0.325388	1.673713
0.329116	1.673289
0.332886	1.672879
0.336699	1.672481
0.340556	1.672096
0.344457	1.671722
0.348402	1.671359
0.352393	1.671008
0.35643	1.670667
0.360513	1.670335
0.364643	1.670014
0.36882	1.669702
0.373044	1.669399
0.377318	1.669105
0.38164	1.668819
0.386011	1.668541
0.390433	1.668271
0.394905	1.668008
0.399429	1.667753
0.404005	1.667504
0.408632	1.667263
0.413313	1.667028
0.418048	1.666799
0.422836	1.666577
0.42768	1.66636
0.432579	1.666149
0.437534	1.665944
0.442546	1.665744
0.447616	1.665549
0.452743	1.665359
0.457929	1.665174
0.463175	1.664994
0.46848	1.664818
0.473847	1.664647
0.479275	1.66448
0.484765	1.664317
0.490318	1.664158
0.495934	1.664003
0.501615	1.663851
0.507361	1.663703
0.513173	1.663559
0.519051	1.663418
0.524997	1.663281
0.531011	1.663146
0.537093	1.663015
0.543246	1.662887
0.549469	1.662761
0.555763	1.662639
0.562129	1.662519
0.568568	1.662402
0.575081	1.662287
0.581669	1.662175
0.588332	1.662065
0.595071	1.661958
0.601887	1.661852
0.608782	1.661749
0.615756	1.661648
0.622809	1.66155
0.629943	1.661453
0.637159	1.661358
0.644458	1.661264
0.65184	1.661173
0.659307	1.661083
0.666859	1.660995
0.674498	1.660909
0.682224	1.660824
0.690039	1.660741
0.697944	1.660659
0.705939	1.660579
0.714025	1.6605
0.722204	1.660422
0.730477	1.660345
0.738845	1.66027
0.747308	1.660196
0.755868	1.660122
0.764527	1.66005
0.773284	1.659979
0.782142	1.659909
0.791102	1.65984
0.800164	1.659772
0.80933	1.659705
0.8186	1.659638
0.827978	1.659573
0.837462	1.659508
0.847055	1.659443
0.856758	1.65938
0.866572	1.659317
0.876499	1.659254
0.886539	1.659193
0.896694	1.659131
0.906966	1.65907
0.917355	1.65901
0.927863	1.65895
0.938492	1.658891
0.949242	1.658831
0.960116	1.658772
0.971114	1.658714
0.982238	1.658655
0.993489	1.658597
1.00487	1.658539
1.01638	1.658482
1.02802	1.658424
1.0398	1.658366
1.05171	1.658309
1.06376	1.658251
1.07594	1.658194
1.08827	1.658136
1.10073	1.658079
1.11334	1.658021
1.1261	1.657963
1.13899	1.657905
1.15204	1.657847
1.16524	1.657789
1.17859	1.65773
1.19209	1.657671
1.20574	1.657612
1.21955	1.657552
1.23352	1.657492
1.24765	1.657432
1.26195	1.657371
1.2764	1.65731
1.29102	1.657248
1.30581	1.657186
1.32077	1.657123
1.3359	1.657059
1.3512	1.656995
1.36668	1.65693
1.38233	1.656865
1.39817	1.656799
1.41418	1.656731
1.43038	1.656664
1.44677	1.656595
1.46334	1.656525
1.4801	1.656455
1.49706	1.656383
1.51421	1.656311
1.53155	1.656237
1.5491	1.656162
1.56684	1.656087
1.58479	1.65601
1.60294	1.655932
1.6213	1.655852
1.63988	1.655772
1.65866	1.65569
1.67766	1.655606
1.69688	1.655522
1.71632	1.655435
1.73598	1.655348
1.75586	1.655258
1.77598	1.655168
1.79632	1.655075
1.8169	1.654981
1.83771	1.654885
1.85876	1.654787
1.88005	1.654688
1.90159	1.654586
1.92337	1.654483
1.9454	1.654378
1.96769	1.65427
1.99023	1.654161
2.01302	1.654049
2.03608	1.653935
2.05941	1.653819
2.083	1.6537
2.10686	1.653579
2.13099	1.653456
2.1554	1.65333
2.18009	1.653201
2.20506	1.653069
2.23032	1.652935
2.25587	1.652798
2.28171	1.652659
2.30785	1.652516
2.33429	1.65237
2.36103	1.652221
2.38807	1.652069
2.41543	1.651913
2.44309	1.651755
2.47108	1.651592
2.49939	1.651427
2.52802	1.651257
2.55697	1.651084
2.58626	1.650907
2.61589	1.650726
2.64585	1.650541
2.67616	1.650352
2.70682	1.650159
2.73782	1.649962
2.76919	1.64976
2.80091	1.649554
2.83299	1.649343
2.86544	1.649127
2.89827	1.648906
2.93147	1.648681
2.96505	1.64845
2.99901	1.648214
3.03336	1.647973
3.06811	1.647726
3.10326	1.647474
3.1388	1.647216
3.17476	1.646952
3.21113	1.646682
3.24791	1.646405
3.28511	1.646123
3.32274	1.645834
3.36081	1.645538
3.3993	1.645236
3.43824	1.644926
3.47763	1.64461
3.51746	1.644286
3.55776	1.643955
3.59851	1.643616
3.63973	1.643269
3.68142	1.642914
3.72359	1.642551
3.76625	1.642179
3.80939	1.641799
3.85303	1.641409
3.89716	1.641011
3.9418	1.640604
3.98696	1.640187
4.03263	1.63976
4.07882	1.639323
4.12554	1.638876
4.1728	1.638419
4.2206	1.63795
4.26895	1.637471
4.31785	1.636981
4.36731	1.636478
4.41734	1.635965
4.46794	1.635438
4.51912	1.6349
4.57088	1.634349
4.62324	1.633785
4.6762	1.633207
4.72977	1.632616
4.78395	1.63201
4.83875	1.63139
4.89417	1.630756
4.95024	1.630106
5.00694	1.629441
5.0643	1.62876
5.12231	1.628063
5.18098	1.627349
5.24033	1.626618
5.30036	1.62587
5.36107	1.625103
5.42248	1.624318
5.4846	1.623515
5.54742	1.622692
5.61097	1.621849
5.67524	1.620985
5.74025	1.620101
5.80601	1.619196
5.87251	1.618268
5.93978	1.617318
6.00782	1.616345
6.07664	1.615348
6.14625	1.614327
6.21666	1.613281
6.28787	1.61221
6.35989	1.611112
6.43275	1.609987
6.50643	1.608835
6.58096	1.607655
6.65635	1.606445
6.7326	1.605206
6.80972	1.603936
6.88772	1.602634
6.96662	1.6013
7.04642	1.599934
7.12714	1.598533
7.20878	1.597097
7.29136	1.595625
7.37488	1.594117
7.45936	1.592571
7.54481	1.590986
7.63123	1.58936
7.71865	1.587694
7.80706	1.585986
7.89649	1.584235
7.98695	1.582439
8.07844	1.580597
8.17098	1.578708
8.26457	1.576771
8.35924	1.574785
8.455	1.572747
8.55185	1.570656
8.64981	1.568512
8.74889	1.566312
8.84911	1.564054
8.95048	1.561738
9.05301	1.559361
9.15671	1.556922
9.2616	1.554419
9.36769	1.551849
9.47499	1.549212
9.58353	1.546504
9.69331	1.543724
9.80435	1.540869
9.91665	1.537938
10.0302	1.534927
10.1451	1.531836
10.2614	1.528659
10.3789	1.525397
10.4978	1.522044
10.618	1.5186
10.7397	1.51506
10.8627	1.511421
10.9871	1.507681
11.113	1.503836
11.2403	1.499883
11.369	1.495817
11.4993	1.491636
11.631	1.487335
11.7642	1.48291
11.899	1.478357
12.0353	1.473671
12.1731	1.468847
12.3126	1.463882
12.4536	1.458769
12.5963	1.453503
12.7406	1.448079
12.8865	1.44249
13.0341	1.436731
13.1834	1.430795
13.3345	1.424675
13.4872	1.418364
13.6417	1.411854
13.798	1.405138
13.956	1.398206
14.1159	1.391051
14.2776	1.383662
14.4411	1.37603
14.6065	1.368145
14.7739	1.359995
14.9431	1.351568
15.1143	1.342852
15.2874	1.333833
15.4625	1.324498
15.6396	1.31483
15.8188	1.304815
16	1.294434

Optical transmission calculator

Free-standing sample in vacuum, normal incidence

Transmittance T: —
Reflectance R: —

Fresnel reflection calculator

R_p: —
R_s: —
R = (R_p+R_s)/2: —
Phase φ_p: —
Phase φ_s: —
Brewster angle θ_B: —
Critical angle θ_C: —

LiCl (Lithium chloride): all datasets

Li 1976: n 0.17–16 µm n 0.17–16 µm default

About LiCl (Lithium chloride)

Lithium chloride (LiCl) is a salt with a range of applications, from hygroscopic uses in air conditioning and industrial drying to a role as a brazing flux for aluminum in metallurgy. In the realm of optics, lithium chloride is employed as a crystal for IR, THz, and far-IR spectroscopy. It has a broad transmission range and is relatively inert, making it useful for specialized applications that require transparency in those wavelength ranges. However, it is highly hygroscopic and must be carefully handled and stored to maintain its optical properties.

More about LiCl (Lithium chloride) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/LiCl/nk/Li.yml
ID: ds_7dd60ee24a7d
API: /v1/datasets/ds_7dd60ee24a7d

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