Optical constants

Refractive index of RbI (Rubidium iodide)

Li 1976: n 0.24–64 µm

Data: formula 1
Range: 0.24–64 µm
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.64761
Extinction coefficient k: 0

Permittivity ε₁: 2.71463
Permittivity ε₂: 0

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

Abbe number V_d: 24.589
Chromatic dispersion dn/dλ: -0.131938 µm⁻¹

Group index n_g: 1.72514
Group velocity dispersion: 276.813 fs²/mm

Dispersion parameter D: -1510.16 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

# RbI (Rubidium iodide): Li 1976: n 0.24–64 µm
rbi = ls.fetch_refractiveindex("main", "RbI", "Li", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(rbi.range_nm)  # (240, 64000) nm
eps = rbi.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_383f8629a678/lightsmith"
rbi = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(rbi.source)  # citation and provenance travel with the data

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

# ... load rbi as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=rbi)],
    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_383f8629a678/lightsmith?model=drude_lorentz"
rbi_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 = 0.60563 + \frac{0.00947 λ^{2}}{λ^{2} - {0.12}^{2}} + \frac{0.01073 λ^{2}}{λ^{2} - {0.134}^{2}} + \frac{0.00136 λ^{2}}{λ^{2} - {0.156}^{2}} + \frac{0.41864 λ^{2}}{λ^{2} - {0.179}^{2}} + \frac{0.41771 λ^{2}}{λ^{2} - {0.187}^{2}} + \frac{0.13707 λ^{2}}{λ^{2} - {0.223}^{2}} + \frac{2.36091 λ^{2}}{λ^{2} - {132.45}^{2}}

Valid from 0.24 to 64.0 µm.

Coefficients as stored

C_i	Value
C1	0.60563
C2	0.00947
C3	0.12
C4	0.01073
C5	0.134
C6	0.00136
C7	0.156
C8	0.41864
C9	0.179
C10	0.41771
C11	0.187
C12	0.13707
C13	0.223
C14	2.36091
C15	132.45

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

RbI (Rubidium iodide), Li 1976: n 0.24–64 µm: n and k versus wavelength
λ (µm)	n
0.24	2.155428
0.243384	2.102725
0.246815	2.06048
0.250295	2.025401
0.253823	1.995529
0.257402	1.969611
0.261031	1.946798
0.264711	1.92649
0.268443	1.908245
0.272228	1.891732
0.276066	1.876692
0.279958	1.86292
0.283905	1.850251
0.287907	1.838551
0.291966	1.827707
0.296083	1.817627
0.300257	1.808229
0.30449	1.799447
0.308783	1.79122
0.313136	1.783499
0.317551	1.776239
0.322028	1.7694
0.326568	1.762948
0.331172	1.756852
0.335841	1.751084
0.340576	1.74562
0.345378	1.740439
0.350247	1.735519
0.355185	1.730842
0.360193	1.726393
0.365271	1.722157
0.370421	1.71812
0.375643	1.714269
0.380939	1.710592
0.38631	1.707081
0.391756	1.703724
0.397279	1.700513
0.40288	1.69744
0.40856	1.694496
0.41432	1.691676
0.420161	1.688972
0.426085	1.686378
0.432092	1.683888
0.438184	1.681498
0.444362	1.679202
0.450627	1.676995
0.45698	1.674874
0.463422	1.672834
0.469956	1.670871
0.476582	1.668981
0.483301	1.667162
0.490114	1.66541
0.497024	1.663722
0.504032	1.662095
0.511138	1.660527
0.518344	1.659015
0.525652	1.657556
0.533063	1.656149
0.540578	1.65479
0.548199	1.653479
0.555928	1.652213
0.563766	1.650991
0.571714	1.64981
0.579774	1.648669
0.587948	1.647567
0.596237	1.646501
0.604643	1.645471
0.613168	1.644475
0.621813	1.643512
0.630579	1.64258
0.639469	1.641679
0.648485	1.640806
0.657628	1.639963
0.666899	1.639146
0.676301	1.638355
0.685836	1.63759
0.695505	1.636849
0.705311	1.636131
0.715255	1.635436
0.725339	1.634763
0.735565	1.63411
0.745935	1.633478
0.756452	1.632866
0.767117	1.632273
0.777932	1.631698
0.788899	1.63114
0.800022	1.6306
0.811301	1.630076
0.822739	1.629568
0.834338	1.629075
0.846101	1.628598
0.85803	1.628135
0.870127	1.627685
0.882394	1.62725
0.894835	1.626827
0.90745	1.626417
0.920244	1.626019
0.933218	1.625633
0.946375	1.625258
0.959717	1.624895
0.973248	1.624542
0.986969	1.624199
1.00088	1.623867
1.01499	1.623544
1.0293	1.623231
1.04382	1.622927
1.05853	1.622632
1.07346	1.622345
1.08859	1.622066
1.10394	1.621796
1.1195	1.621533
1.13528	1.621278
1.15129	1.621031
1.16752	1.62079
1.18398	1.620557
1.20067	1.620329
1.2176	1.620109
1.23477	1.619895
1.25218	1.619686
1.26983	1.619484
1.28773	1.619287
1.30589	1.619096
1.3243	1.618911
1.34297	1.61873
1.3619	1.618555
1.3811	1.618384
1.40058	1.618218
1.42032	1.618057
1.44035	1.6179
1.46065	1.617748
1.48125	1.6176
1.50213	1.617456
1.52331	1.617315
1.54478	1.617179
1.56656	1.617046
1.58865	1.616917
1.61105	1.616792
1.63376	1.61667
1.65679	1.616551
1.68015	1.616435
1.70384	1.616323
1.72786	1.616213
1.75222	1.616106
1.77692	1.616002
1.80198	1.615901
1.82738	1.615803
1.85314	1.615707
1.87927	1.615613
1.90576	1.615522
1.93263	1.615433
1.95988	1.615347
1.98751	1.615262
2.01553	1.61518
2.04395	1.6151
2.07276	1.615022
2.10199	1.614945
2.13162	1.614871
2.16168	1.614798
2.19215	1.614727
2.22306	1.614658
2.2544	1.61459
2.28618	1.614524
2.31841	1.61446
2.3511	1.614396
2.38425	1.614335
2.41786	1.614274
2.45195	1.614215
2.48652	1.614158
2.52157	1.614101
2.55712	1.614046
2.59318	1.613991
2.62974	1.613938
2.66681	1.613886
2.70441	1.613835
2.74254	1.613784
2.7812	1.613735
2.82041	1.613687
2.86018	1.613639
2.9005	1.613592
2.94139	1.613546
2.98286	1.613501
3.02492	1.613456
3.06756	1.613412
3.11081	1.613369
3.15467	1.613326
3.19914	1.613283
3.24425	1.613242
3.28999	1.6132
3.33637	1.613159
3.38341	1.613119
3.43111	1.613079
3.47948	1.613039
3.52854	1.613
3.57828	1.612961
3.62873	1.612922
3.67989	1.612883
3.73177	1.612845
3.78438	1.612807
3.83774	1.612768
3.89185	1.61273
3.94671	1.612692
4.00236	1.612655
4.05878	1.612617
4.11601	1.612579
4.17404	1.612541
4.23288	1.612503
4.29256	1.612464
4.35308	1.612426
4.41445	1.612388
4.47669	1.612349
4.5398	1.61231
4.60381	1.612271
4.66871	1.612232
4.73453	1.612192
4.80128	1.612152
4.86897	1.612111
4.93762	1.61207
5.00723	1.612029
5.07783	1.611987
5.14942	1.611945
5.22201	1.611902
5.29564	1.611858
5.3703	1.611814
5.44601	1.611769
5.52279	1.611724
5.60065	1.611678
5.67961	1.611631
5.75969	1.611583
5.84089	1.611534
5.92324	1.611485
6.00675	1.611434
6.09143	1.611383
6.17731	1.611331
6.2644	1.611277
6.35272	1.611223
6.44229	1.611167
6.53311	1.611111
6.62522	1.611053
6.71862	1.610993
6.81335	1.610933
6.9094	1.610871
7.00682	1.610808
7.1056	1.610743
7.20578	1.610677
7.30737	1.610609
7.41039	1.61054
7.51487	1.610469
7.62081	1.610396
7.72826	1.610321
7.83721	1.610245
7.94771	1.610166
8.05976	1.610086
8.17339	1.610004
8.28862	1.609919
8.40548	1.609833
8.52398	1.609744
8.64415	1.609653
8.76602	1.609559
8.88961	1.609463
9.01494	1.609365
9.14204	1.609264
9.27093	1.60916
9.40163	1.609053
9.53418	1.608944
9.6686	1.608831
9.80491	1.608716
9.94314	1.608597
10.0833	1.608476
10.2255	1.60835
10.3696	1.608222
10.5158	1.60809
10.6641	1.607954
10.8145	1.607814
10.9669	1.607671
11.1215	1.607523
11.2783	1.607372
11.4373	1.607216
11.5986	1.607055
11.7621	1.606891
11.9279	1.606721
12.0961	1.606547
12.2666	1.606368
12.4396	1.606184
12.615	1.605995
12.7928	1.6058
12.9732	1.6056
13.1561	1.605393
13.3416	1.605182
13.5296	1.604963
13.7204	1.604739
13.9138	1.604508
14.11	1.604271
14.3089	1.604027
14.5107	1.603776
14.7152	1.603517
14.9227	1.603251
15.1331	1.602977
15.3464	1.602696
15.5628	1.602406
15.7822	1.602107
16.0047	1.6018
16.2304	1.601484
16.4592	1.601159
16.6912	1.600824
16.9265	1.60048
17.1652	1.600125
17.4072	1.59976
17.6526	1.599384
17.9015	1.598997
18.1539	1.598598
18.4098	1.598188
18.6694	1.597765
18.9326	1.59733
19.1995	1.596882
19.4702	1.596421
19.7447	1.595946
20.023	1.595456
20.3053	1.594952
20.5916	1.594433
20.8819	1.593898
21.1763	1.593347
21.4749	1.59278
21.7776	1.592195
22.0847	1.591593
22.396	1.590972
22.7118	1.590332
23.032	1.589673
23.3567	1.588994
23.686	1.588294
24.0199	1.587572
24.3586	1.586828
24.702	1.586061
25.0502	1.585271
25.4034	1.584456
25.7616	1.583615
26.1248	1.582749
26.4931	1.581855
26.8666	1.580933
27.2454	1.579982
27.6295	1.579002
28.019	1.57799
28.414	1.576946
28.8146	1.575869
29.2209	1.574757
29.6328	1.57361
30.0506	1.572426
30.4743	1.571204
30.9039	1.569942
31.3396	1.568639
31.7815	1.567293
32.2295	1.565903
32.6839	1.564468
33.1447	1.562985
33.612	1.561452
34.0859	1.559869
34.5664	1.558232
35.0538	1.55654
35.548	1.554791
36.0491	1.552983
36.5574	1.551112
37.0728	1.549177
37.5955	1.547175
38.1255	1.545104
38.663	1.542959
39.2081	1.54074
39.7609	1.538441
40.3214	1.536061
40.8899	1.533595
41.4664	1.53104
42.051	1.528392
42.6439	1.525646
43.2451	1.522799
43.8548	1.519846
44.473	1.516782
45.1	1.513602
45.7359	1.510301
46.3807	1.506873
47.0346	1.503311
47.6977	1.499609
48.3702	1.495761
49.0521	1.491758
49.7437	1.487594
50.445	1.48326
51.1562	1.478746
51.8774	1.474044
52.6088	1.469143
53.3505	1.464033
54.1026	1.458701
54.8654	1.453135
55.6389	1.447321
56.4234	1.441246
57.2188	1.434892
58.0255	1.428243
58.8436	1.421281
59.6732	1.413986
60.5145	1.406335
61.3677	1.398305
62.2329	1.38987
63.1102	1.381002
64	1.37167

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: —

RbI (Rubidium iodide): all datasets

Li 1976: n 0.24–64 µm n 0.24–64 µm default

About RbI (Rubidium iodide)

Rubidium iodide (RbI) is a chemical compound formed by combining rubidium cations (Rb⁺) with iodide anions (I^-). It appears as white or colorless crystalline solid and is highly soluble in water, similar to other alkali metal iodides. In the laboratory, rubidium iodide is used primarily for research purposes, especially in the preparation of other rubidium-based compounds. Due to its high solubility and reactivity, especially with moisture, it should be handled with care and stored in dry conditions or under an inert atmosphere to prevent decomposition or reactions.

More about RbI (Rubidium iodide) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/RbI/nk/Li.yml
ID: ds_383f8629a678
API: /v1/datasets/ds_383f8629a678

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