Optical constants

Refractive index of RbF (Rubidium fluoride)

Li 1976: n 0.15–25 µm

Data: formula 1
Range: 0.15–25 µm
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.39805
Extinction coefficient k: 0

Permittivity ε₁: 1.95454
Permittivity ε₂: 0

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

Abbe number V_d: 63.135
Chromatic dispersion dn/dλ: -0.0322461 µm⁻¹

Group index n_g: 1.417
Group velocity dispersion: 61.3342 fs²/mm

Dispersion parameter D: -334.611 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

# RbF (Rubidium fluoride): Li 1976: n 0.15–25 µm
rbf = ls.fetch_refractiveindex("main", "RbF", "Li", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(rbf.range_nm)  # (150, 25000) nm
eps = rbf.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_385735d8a1ca/lightsmith"
rbf = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(rbf.source)  # citation and provenance travel with the data

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

# ... load rbf as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=rbf)],
    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_385735d8a1ca/lightsmith?model=drude_lorentz"
rbf_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 = 0.395 + \frac{0.535 λ^{2}}{λ^{2} - {0.124}^{2}} + \frac{4.55 λ^{2}}{λ^{2} - {63.29}^{2}}

Valid from 0.15 to 25.0 µm.

Coefficients as stored

C_i	Value
C1	0.395
C2	0.535
C3	0.124
C4	4.55
C5	63.29

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 derivation is based on a single data point and knowledge of the dielectric constants and the characteristic absorption peaks.

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

RbF (Rubidium fluoride), Li 1976: n 0.15–25 µm: n and k versus wavelength
λ (µm)	n
0.15	1.756327
0.151936	1.731223
0.153896	1.708833
0.155882	1.688741
0.157894	1.670612
0.159931	1.654174
0.161995	1.639204
0.164086	1.625517
0.166203	1.612956
0.168348	1.601391
0.170521	1.590711
0.172721	1.58082
0.17495	1.571637
0.177208	1.563089
0.179494	1.555117
0.181811	1.547665
0.184157	1.540686
0.186533	1.534139
0.18894	1.527986
0.191379	1.522194
0.193848	1.516735
0.19635	1.511582
0.198884	1.506711
0.20145	1.502101
0.20405	1.497734
0.206683	1.493591
0.20935	1.489657
0.212052	1.485919
0.214788	1.482361
0.21756	1.478974
0.220368	1.475746
0.223211	1.472667
0.226092	1.469728
0.229009	1.46692
0.231965	1.464236
0.234958	1.461668
0.23799	1.45921
0.241061	1.456856
0.244172	1.454599
0.247323	1.452436
0.250515	1.45036
0.253747	1.448367
0.257022	1.446453
0.260339	1.444614
0.263698	1.442846
0.267101	1.441146
0.270548	1.43951
0.274039	1.437935
0.277576	1.436418
0.281158	1.434957
0.284786	1.43355
0.288461	1.432192
0.292183	1.430884
0.295954	1.429621
0.299773	1.428403
0.303642	1.427227
0.30756	1.426091
0.311529	1.424994
0.315549	1.423935
0.319621	1.422911
0.323746	1.421921
0.327923	1.420964
0.332155	1.420039
0.336441	1.419144
0.340783	1.418278
0.345181	1.41744
0.349635	1.416628
0.354147	1.415843
0.358717	1.415082
0.363346	1.414346
0.368035	1.413632
0.372784	1.412941
0.377595	1.412271
0.382468	1.411621
0.387403	1.410992
0.392403	1.410381
0.397467	1.409789
0.402596	1.409215
0.407791	1.408658
0.413053	1.408118
0.418384	1.407594
0.423783	1.407085
0.429251	1.406592
0.434791	1.406113
0.440402	1.405647
0.446085	1.405196
0.451841	1.404757
0.457672	1.404331
0.463578	1.403917
0.469561	1.403515
0.47562	1.403125
0.481758	1.402745
0.487975	1.402377
0.494272	1.402018
0.50065	1.40167
0.507111	1.401332
0.513655	1.401003
0.520283	1.400683
0.526997	1.400371
0.533798	1.400069
0.540687	1.399775
0.547664	1.399488
0.554731	1.39921
0.56189	1.398939
0.569141	1.398675
0.576485	1.398419
0.583925	1.398169
0.59146	1.397927
0.599093	1.39769
0.606824	1.39746
0.614654	1.397236
0.622586	1.397018
0.630621	1.396805
0.638758	1.396599
0.647001	1.396397
0.655351	1.396201
0.663808	1.39601
0.672374	1.395823
0.681051	1.395642
0.689839	1.395465
0.698741	1.395293
0.707758	1.395125
0.716892	1.394961
0.726143	1.394801
0.735513	1.394646
0.745005	1.394494
0.754619	1.394346
0.764357	1.394201
0.774221	1.39406
0.784212	1.393923
0.794332	1.393788
0.804582	1.393657
0.814965	1.39353
0.825482	1.393405
0.836134	1.393283
0.846924	1.393164
0.857854	1.393047
0.868924	1.392934
0.880137	1.392822
0.891495	1.392714
0.902999	1.392608
0.914652	1.392504
0.926455	1.392402
0.938411	1.392303
0.95052	1.392205
0.962787	1.39211
0.975211	1.392017
0.987796	1.391926
1.00054	1.391836
1.01345	1.391749
1.02653	1.391663
1.03978	1.391578
1.0532	1.391496
1.06679	1.391414
1.08056	1.391335
1.0945	1.391257
1.10862	1.39118
1.12293	1.391104
1.13742	1.39103
1.1521	1.390957
1.16697	1.390885
1.18203	1.390815
1.19728	1.390745
1.21273	1.390677
1.22838	1.390609
1.24423	1.390542
1.26029	1.390476
1.27655	1.390412
1.29302	1.390347
1.30971	1.390284
1.32661	1.390221
1.34373	1.390159
1.36107	1.390098
1.37863	1.390037
1.39643	1.389977
1.41445	1.389917
1.4327	1.389858
1.45119	1.389799
1.46991	1.389741
1.48888	1.389682
1.5081	1.389625
1.52756	1.389567
1.54727	1.38951
1.56724	1.389453
1.58746	1.389396
1.60795	1.389339
1.6287	1.389282
1.64971	1.389225
1.671	1.389168
1.69257	1.389111
1.71441	1.389054
1.73653	1.388997
1.75894	1.38894
1.78164	1.388883
1.80463	1.388825
1.82792	1.388767
1.85151	1.388709
1.8754	1.388651
1.8996	1.388592
1.92412	1.388532
1.94895	1.388472
1.9741	1.388412
1.99957	1.388351
2.02538	1.38829
2.05151	1.388228
2.07799	1.388165
2.1048	1.388101
2.13196	1.388037
2.15948	1.387972
2.18734	1.387906
2.21557	1.387839
2.24416	1.387772
2.27312	1.387703
2.30245	1.387633
2.33217	1.387563
2.36226	1.387491
2.39275	1.387418
2.42362	1.387344
2.4549	1.387268
2.48658	1.387191
2.51867	1.387113
2.55117	1.387033
2.58409	1.386952
2.61744	1.38687
2.65121	1.386786
2.68543	1.3867
2.72008	1.386612
2.75518	1.386523
2.79074	1.386432
2.82675	1.386339
2.86323	1.386245
2.90018	1.386148
2.9376	1.386049
2.97551	1.385948
3.01391	1.385845
3.0528	1.385739
3.0922	1.385631
3.1321	1.385521
3.17252	1.385409
3.21346	1.385293
3.25493	1.385176
3.29693	1.385055
3.33948	1.384932
3.38257	1.384805
3.42622	1.384676
3.47044	1.384544
3.51522	1.384409
3.56059	1.38427
3.60653	1.384128
3.65307	1.383983
3.70022	1.383834
3.74797	1.383681
3.79633	1.383525
3.84532	1.383365
3.89494	1.383201
3.94521	1.383033
3.99612	1.382861
4.04769	1.382684
4.09992	1.382503
4.15283	1.382318
4.20642	1.382128
4.2607	1.381933
4.31568	1.381733
4.37138	1.381528
4.42779	1.381318
4.48493	1.381103
4.5428	1.380882
4.60142	1.380656
4.6608	1.380424
4.72095	1.380185
4.78187	1.379941
4.84358	1.37969
4.90608	1.379433
4.9694	1.379169
5.03352	1.378899
5.09848	1.378621
5.16427	1.378336
5.23092	1.378044
5.29842	1.377744
5.36679	1.377437
5.43605	1.377121
5.5062	1.376797
5.57725	1.376465
5.64923	1.376123
5.72213	1.375773
5.79597	1.375414
5.87076	1.375045
5.94652	1.374667
6.02326	1.374278
6.10099	1.373879
6.17972	1.37347
6.25947	1.373049
6.34024	1.372618
6.42206	1.372175
6.50494	1.37172
6.58888	1.371253
6.67391	1.370774
6.76003	1.370282
6.84727	1.369777
6.93563	1.369258
7.02513	1.368725
7.11578	1.368178
7.20761	1.367616
7.30062	1.367039
7.39483	1.366446
7.49026	1.365838
7.58692	1.365213
7.68483	1.364571
7.784	1.363911
7.88444	1.363234
7.98619	1.362538
8.08925	1.361823
8.19364	1.361089
8.29937	1.360335
8.40647	1.359559
8.51496	1.358763
8.62484	1.357945
8.73614	1.357104
8.84887	1.35624
8.96307	1.355352
9.07873	1.35444
9.19589	1.353502
9.31456	1.352539
9.43476	1.351548
9.55651	1.35053
9.67983	1.349483
9.80475	1.348407
9.93127	1.347301
10.0594	1.346164
10.1892	1.344995
10.3207	1.343793
10.4539	1.342556
10.5888	1.341285
10.7255	1.339977
10.8639	1.338632
11.0041	1.337249
11.1461	1.335826
11.2899	1.334362
11.4356	1.332856
11.5832	1.331306
11.7326	1.329711
11.8841	1.32807
12.0374	1.326382
12.1927	1.324643
12.3501	1.322854
12.5095	1.321012
12.6709	1.319115
12.8344	1.317163
13	1.315152
13.1678	1.313081
13.3377	1.310948
13.5098	1.30875
13.6842	1.306487
13.8608	1.304154
14.0396	1.301751
14.2208	1.299273
14.4043	1.29672
14.5902	1.294088
14.7785	1.291374
14.9692	1.288575
15.1624	1.285688
15.358	1.282711
15.5562	1.279639
15.757	1.276469
15.9603	1.273198
16.1663	1.269821
16.3749	1.266334
16.5862	1.262734
16.8002	1.259015
17.017	1.255174
17.2366	1.251205
17.4591	1.247102
17.6844	1.242861
17.9126	1.238476
18.1437	1.23394
18.3779	1.229248
18.615	1.224392
18.8552	1.219366
19.0986	1.214161
19.345	1.208771
19.5947	1.203185
19.8475	1.197396
20.1036	1.191394
20.3631	1.185168
20.6259	1.178709
20.892	1.172004
21.1616	1.16504
21.4347	1.157806
21.7113	1.150287
21.9915	1.142467
22.2753	1.134331
22.5627	1.125861
22.8539	1.117038
23.1488	1.107843
23.4475	1.098252
23.7501	1.088243
24.0566	1.07779
24.367	1.066863
24.6815	1.055433
25	1.043466

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: —

RbF (Rubidium fluoride): all datasets

Li 1976: n 0.15–25 µm n 0.15–25 µm default

About RbF (Rubidium fluoride)

Rubidium fluoride (RbF) is a chemical compound formed by the union of rubidium cations (Rb⁺) and fluoride anions (F^-). The compound manifests as a white or colorless crystalline solid. Like other alkali metal fluorides, RbF is highly soluble in water. In laboratories, rubidium fluoride is utilized mainly for research purposes, particularly in the synthesis of other rubidium-containing compounds. Owing to its high reactivity, especially when exposed to moisture or water, it's essential to handle and store RbF with care, typically under an inert atmosphere or in a desiccated environment.

More about RbF (Rubidium fluoride) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/RbF/nk/Li.yml
ID: ds_385735d8a1ca
API: /v1/datasets/ds_385735d8a1ca

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