Optical constants

Refractive index of CH₄N₂O (Urea)

Rosker et al. 1985: n(o) 0.3–1.06 µm

Data: formula 4
Range: 0.3–1.06 µm
Optical axis: o
Licence: CC0-1.0

Uniaxial crystal, axes: oe

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.49062
Extinction coefficient k: 0

Permittivity ε₁: 2.22195
Permittivity ε₂: 0

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

Abbe number V_d: 49.84
Chromatic dispersion dn/dλ: -0.0495735 µm⁻¹

Group index n_g: 1.51975
Group velocity dispersion: 101.876 fs²/mm

Dispersion parameter D: -555.786 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

# CH4N2O (Urea): Rosker et al. 1985: n(o) 0.3–1.06 µm
ch4n2o = ls.fetch_refractiveindex("organic", "urea", "Rosker-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ch4n2o.range_nm)  # (300, 1060) nm
eps = ch4n2o.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_ca3125162f9a/lightsmith"
ch4n2o = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(ch4n2o.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (urea/rosker-1985-o).

# ... load ch4n2o as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=ch4n2o)],
    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"]).

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

RefractiveIndex.INFO (formula 4), λ in µm

n^{2} = 2.1823 + \frac{0.0125 λ^{0.0}}{λ^{2} - {0.03}^{1.0}}

Valid from 0.3 to 1.06 µm.

Coefficients as stored

C_i	Value
C1	2.1823
C2	0.0125
C3	0.0
C4	0.03
C5	1.0
C6	0.0
C7	0.0
C8	0.0
C9	1.0

Comments and conditions

Room temperature. Ordinary ray (o).

Conditions

direction: o

References

M. J. Rosker, K. Cheng, C. L. Tang. Practical urea optical parametric oscillator for tunable generation throughout the visible and near-infrared. IEEE J. Quantum Electron. 21 1600-1606 (1985)

doi:10.1109/jqe.1985.1072557 Practical urea optical parametric oscillator for tunable generation throughout the visible and near-infrared, IEEE Journal of Quantum Electronics (1985)

Cite

M. Rosker, K. Cheng and C. Tang. Practical urea optical parametric oscillator for tunable generation throughout the visible and near-infrared. IEEE Journal of Quantum Electronics, 21, 1600-1606 (1985), doi:10.1109/jqe.1985.1072557; 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

CH4N2O (Urea), Rosker et al. 1985: n(o) 0.3–1.06 µm: n and k versus wavelength
λ (µm)	n
0.3	1.546167
0.300951	1.545532
0.301904	1.544904
0.302861	1.544284
0.30382	1.543671
0.304783	1.543066
0.305749	1.542467
0.306717	1.541876
0.307689	1.541292
0.308664	1.540715
0.309642	1.540144
0.310623	1.53958
0.311608	1.539023
0.312595	1.538472
0.313585	1.537927
0.314579	1.537389
0.315576	1.536857
0.316576	1.536331
0.317579	1.53581
0.318585	1.535296
0.319594	1.534788
0.320607	1.534285
0.321623	1.533787
0.322642	1.533296
0.323664	1.532809
0.32469	1.532329
0.325719	1.531853
0.326751	1.531383
0.327786	1.530917
0.328825	1.530457
0.329866	1.530002
0.330912	1.529551
0.33196	1.529106
0.333012	1.528665
0.334067	1.528229
0.335126	1.527798
0.336187	1.527371
0.337253	1.526949
0.338321	1.526531
0.339393	1.526118
0.340469	1.525708
0.341547	1.525304
0.34263	1.524903
0.343715	1.524506
0.344804	1.524114
0.345897	1.523726
0.346993	1.523341
0.348092	1.522961
0.349195	1.522584
0.350302	1.522211
0.351412	1.521842
0.352525	1.521477
0.353642	1.521115
0.354763	1.520757
0.355887	1.520403
0.357014	1.520052
0.358145	1.519705
0.35928	1.519361
0.360419	1.51902
0.361561	1.518683
0.362706	1.518349
0.363855	1.518019
0.365008	1.517692
0.366165	1.517367
0.367325	1.517046
0.368489	1.516728
0.369657	1.516414
0.370828	1.516102
0.372003	1.515793
0.373181	1.515487
0.374364	1.515184
0.37555	1.514884
0.37674	1.514587
0.377934	1.514293
0.379131	1.514001
0.380333	1.513712
0.381538	1.513426
0.382747	1.513143
0.383959	1.512862
0.385176	1.512584
0.386396	1.512308
0.387621	1.512035
0.388849	1.511765
0.390081	1.511497
0.391317	1.511231
0.392557	1.510968
0.393801	1.510707
0.395048	1.510449
0.3963	1.510193
0.397556	1.50994
0.398815	1.509688
0.400079	1.509439
0.401347	1.509193
0.402618	1.508948
0.403894	1.508706
0.405174	1.508466
0.406458	1.508228
0.407746	1.507992
0.409037	1.507758
0.410334	1.507526
0.411634	1.507297
0.412938	1.507069
0.414246	1.506843
0.415559	1.50662
0.416876	1.506398
0.418196	1.506178
0.419522	1.505961
0.420851	1.505745
0.422184	1.505531
0.423522	1.505319
0.424864	1.505108
0.42621	1.5049
0.427561	1.504693
0.428915	1.504488
0.430274	1.504285
0.431638	1.504084
0.433005	1.503884
0.434377	1.503686
0.435754	1.50349
0.437134	1.503296
0.438519	1.503103
0.439909	1.502912
0.441303	1.502722
0.442701	1.502534
0.444104	1.502348
0.445511	1.502163
0.446922	1.501979
0.448339	1.501798
0.449759	1.501617
0.451184	1.501439
0.452614	1.501261
0.454048	1.501086
0.455487	1.500911
0.45693	1.500739
0.458378	1.500567
0.45983	1.500397
0.461287	1.500229
0.462749	1.500062
0.464215	1.499896
0.465686	1.499731
0.467161	1.499568
0.468641	1.499406
0.470126	1.499246
0.471616	1.499087
0.47311	1.498929
0.474609	1.498773
0.476113	1.498617
0.477622	1.498463
0.479135	1.498311
0.480653	1.498159
0.482176	1.498009
0.483704	1.49786
0.485237	1.497712
0.486774	1.497565
0.488316	1.49742
0.489864	1.497275
0.491416	1.497132
0.492973	1.49699
0.494535	1.496849
0.496102	1.496709
0.497674	1.496571
0.499251	1.496433
0.500832	1.496297
0.502419	1.496161
0.504011	1.496027
0.505608	1.495894
0.50721	1.495762
0.508817	1.49563
0.51043	1.4955
0.512047	1.495371
0.513669	1.495243
0.515297	1.495116
0.51693	1.49499
0.518568	1.494865
0.520211	1.494741
0.521859	1.494617
0.523512	1.494495
0.525171	1.494374
0.526835	1.494254
0.528504	1.494134
0.530179	1.494016
0.531859	1.493898
0.533544	1.493782
0.535235	1.493666
0.536931	1.493551
0.538632	1.493437
0.540339	1.493324
0.542051	1.493212
0.543768	1.4931
0.545491	1.49299
0.547219	1.49288
0.548953	1.492771
0.550693	1.492663
0.552438	1.492556
0.554188	1.49245
0.555944	1.492344
0.557705	1.492239
0.559473	1.492135
0.561245	1.492032
0.563024	1.49193
0.564808	1.491828
0.566597	1.491727
0.568392	1.491627
0.570193	1.491528
0.572	1.491429
0.573812	1.491331
0.575631	1.491234
0.577455	1.491138
0.579284	1.491042
0.58112	1.490947
0.582961	1.490853
0.584808	1.49076
0.586661	1.490667
0.58852	1.490575
0.590385	1.490483
0.592255	1.490392
0.594132	1.490302
0.596014	1.490213
0.597903	1.490124
0.599797	1.490036
0.601698	1.489948
0.603604	1.489862
0.605517	1.489775
0.607435	1.48969
0.60936	1.489605
0.611291	1.489521
0.613228	1.489437
0.615171	1.489354
0.61712	1.489271
0.619075	1.489189
0.621037	1.489108
0.623005	1.489028
0.624979	1.488947
0.626959	1.488868
0.628945	1.488789
0.630938	1.488711
0.632937	1.488633
0.634943	1.488556
0.636955	1.488479
0.638973	1.488403
0.640998	1.488328
0.643029	1.488253
0.645066	1.488178
0.64711	1.488104
0.64916	1.488031
0.651217	1.487958
0.653281	1.487886
0.65535	1.487814
0.657427	1.487743
0.65951	1.487672
0.6616	1.487602
0.663696	1.487532
0.665799	1.487463
0.667909	1.487394
0.670025	1.487326
0.672148	1.487258
0.674278	1.487191
0.676414	1.487124
0.678557	1.487058
0.680707	1.486992
0.682864	1.486926
0.685028	1.486861
0.687198	1.486797
0.689376	1.486733
0.69156	1.486669
0.693751	1.486606
0.695949	1.486544
0.698155	1.486481
0.700367	1.48642
0.702586	1.486358
0.704812	1.486298
0.707045	1.486237
0.709285	1.486177
0.711533	1.486117
0.713787	1.486058
0.716049	1.486
0.718318	1.485941
0.720594	1.485883
0.722877	1.485826
0.725167	1.485769
0.727465	1.485712
0.72977	1.485656
0.732082	1.4856
0.734402	1.485544
0.736729	1.485489
0.739063	1.485434
0.741405	1.48538
0.743754	1.485326
0.746111	1.485272
0.748475	1.485219
0.750847	1.485166
0.753226	1.485114
0.755612	1.485061
0.758006	1.48501
0.760408	1.484958
0.762818	1.484907
0.765235	1.484857
0.767659	1.484806
0.770092	1.484756
0.772532	1.484707
0.774979	1.484657
0.777435	1.484608
0.779898	1.48456
0.782369	1.484511
0.784848	1.484463
0.787335	1.484416
0.78983	1.484368
0.792332	1.484322
0.794843	1.484275
0.797361	1.484229
0.799888	1.484183
0.802422	1.484137
0.804965	1.484091
0.807515	1.484046
0.810074	1.484002
0.812641	1.483957
0.815216	1.483913
0.817799	1.483869
0.82039	1.483826
0.822989	1.483783
0.825597	1.48374
0.828213	1.483697
0.830837	1.483655
0.83347	1.483613
0.83611	1.483571
0.83876	1.483529
0.841417	1.483488
0.844083	1.483447
0.846758	1.483407
0.849441	1.483366
0.852132	1.483326
0.854832	1.483286
0.857541	1.483247
0.860258	1.483208
0.862984	1.483169
0.865718	1.48313
0.868461	1.483091
0.871213	1.483053
0.873973	1.483015
0.876743	1.482977
0.879521	1.48294
0.882307	1.482903
0.885103	1.482866
0.887907	1.482829
0.890721	1.482793
0.893543	1.482757
0.896374	1.482721
0.899214	1.482685
0.902064	1.48265
0.904922	1.482614
0.907789	1.482579
0.910665	1.482545
0.913551	1.48251
0.916445	1.482476
0.919349	1.482442
0.922262	1.482408
0.925184	1.482374
0.928116	1.482341
0.931057	1.482308
0.934007	1.482275
0.936966	1.482242
0.939935	1.48221
0.942913	1.482178
0.945901	1.482146
0.948898	1.482114
0.951905	1.482082
0.954921	1.482051
0.957946	1.48202
0.960982	1.481989
0.964027	1.481958
0.967081	1.481927
0.970145	1.481897
0.973219	1.481867
0.976303	1.481837
0.979396	1.481807
0.9825	1.481778
0.985613	1.481748
0.988736	1.481719
0.991868	1.48169
0.995011	1.481661
0.998164	1.481633
1.00133	1.481604
1.0045	1.481576
1.00768	1.481548
1.01087	1.48152
1.01408	1.481493
1.01729	1.481465
1.02051	1.481438
1.02375	1.481411
1.02699	1.481384
1.03025	1.481357
1.03351	1.481331
1.03678	1.481304
1.04007	1.481278
1.04337	1.481252
1.04667	1.481226
1.04999	1.481201
1.05331	1.481175
1.05665	1.48115
1.06	1.481125

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: —

CH₄N₂O (Urea): all datasets

About CH4N2O (Urea)

Urea (CH₄N₂O) is an organic compound that appears as white crystalline solid. It is highly soluble in water and is the primary nitrogenous end product of protein metabolism, produced by the liver and released into the bloodstream to be eliminated by the kidneys in the urine. Urea is also synthesized on an industrial scale worldwide and has a variety of applications. One of its most common uses is as a nitrogen-release fertilizer, providing an accessible nitrogen source for plant growth. Additionally, urea finds applications in the production of resins and plastics, and it is a component in many cosmetic and skincare products for its moisturizing properties. In the realm of optics, urea is notable for its ability to form birefringent crystals and has been used in some optical devices. However, when handling urea, especially in industrial settings, it's important to note that prolonged exposure can cause mild skin or eye irritation. Chemical formula: CO(NH₂)₂

More about CH4N2O (Urea) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/organic/CH4N2O - urea/nk/Rosker-o.yml
ID: ds_ca3125162f9a
API: /v1/datasets/ds_ca3125162f9a

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