Optical constants

Refractive index of C₁₈H₃₄O₂ (Oleic acid)

Jones et al. 2015: n 0.595–0.670 µm

Data: formula 5
Range: 0.495–0.67 µm
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.46946
Extinction coefficient k: 0

Permittivity ε₁: 2.15931
Permittivity ε₂: 0

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

Abbe number V_d: —
Chromatic dispersion dn/dλ: -0.0507115 µm⁻¹

Group index n_g: 1.49926
Group velocity dispersion: 100.001 fs²/mm

Dispersion parameter D: -545.561 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

# C18H34O2 (Oleic acid): Jones et al. 2015: n 0.595–0.670 µm
c18h34o2 = ls.fetch_refractiveindex("organic", "oleic_acid", "Jones", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(c18h34o2.range_nm)  # (495, 670) nm
eps = c18h34o2.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_4c228191f2a4/lightsmith"
c18h34o2 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(c18h34o2.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (oleic-acid/jones-2015).

# ... load c18h34o2 as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=c18h34o2)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=495, stop_nm=670, 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

Cauchy (formula 5), λ in µm

n = 1.4554 + 0.004565 λ^{- 2.0} + 0.0001 λ^{- 4.0}

Valid from 0.495 to 0.67 µm.

Coefficients as stored

C_i	Value
C1	1.4554
C2	0.004565
C3	-2.0
C4	0.0001
C5	-4.0

Comments and conditions

Optically trapped oleic acid droplets of ~1 µm radius.

References

S. H. Jones, M. D. King, A. D. Ward. Atmospherically relevant core–shell aerosol studied using optical trapping and Mie scattering. Chem. Commun. 51, 4914-4917 (2015)

doi:10.1039/c4cc09835h Atmospherically relevant core–shell aerosol studied using optical trapping and Mie scattering, Chemical Communications (2015)

Cite

S. H. Jones, M. D. King and A. D. Ward. Atmospherically relevant core–shell aerosol studied using optical trapping and Mie scattering. Chemical Communications, 51, 4914-4917 (2015), doi:10.1039/c4cc09835h; 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

C18H34O2 (Oleic acid), Jones et al. 2015: n 0.595–0.670 µm: n and k versus wavelength
λ (µm)	n
0.495	1.475696
0.495376	1.475663
0.495752	1.47563
0.496128	1.475597
0.496505	1.475564
0.496881	1.47553
0.497258	1.475497
0.497636	1.475465
0.498014	1.475432
0.498392	1.475399
0.49877	1.475366
0.499148	1.475333
0.499527	1.475301
0.499906	1.475268
0.500286	1.475235
0.500665	1.475203
0.501045	1.475171
0.501426	1.475138
0.501806	1.475106
0.502187	1.475074
0.502568	1.475041
0.50295	1.475009
0.503332	1.474977
0.503714	1.474945
0.504096	1.474913
0.504478	1.474881
0.504861	1.474849
0.505245	1.474817
0.505628	1.474786
0.506012	1.474754
0.506396	1.474722
0.50678	1.474691
0.507165	1.474659
0.50755	1.474628
0.507935	1.474596
0.50832	1.474565
0.508706	1.474534
0.509092	1.474502
0.509479	1.474471
0.509865	1.47444
0.510252	1.474409
0.51064	1.474378
0.511027	1.474347
0.511415	1.474316
0.511803	1.474285
0.512192	1.474254
0.512581	1.474223
0.51297	1.474193
0.513359	1.474162
0.513749	1.474131
0.514138	1.474101
0.514529	1.47407
0.514919	1.47404
0.51531	1.474009
0.515701	1.473979
0.516093	1.473949
0.516484	1.473918
0.516876	1.473888
0.517269	1.473858
0.517661	1.473828
0.518054	1.473798
0.518447	1.473768
0.518841	1.473738
0.519235	1.473708
0.519629	1.473678
0.520023	1.473648
0.520418	1.473619
0.520813	1.473589
0.521208	1.473559
0.521604	1.47353
0.521999	1.4735
0.522396	1.473471
0.522792	1.473441
0.523189	1.473412
0.523586	1.473383
0.523983	1.473353
0.524381	1.473324
0.524779	1.473295
0.525177	1.473266
0.525576	1.473237
0.525975	1.473208
0.526374	1.473179
0.526774	1.47315
0.527173	1.473121
0.527574	1.473092
0.527974	1.473063
0.528375	1.473034
0.528776	1.473006
0.529177	1.472977
0.529579	1.472949
0.529981	1.47292
0.530383	1.472892
0.530785	1.472863
0.531188	1.472835
0.531591	1.472806
0.531995	1.472778
0.532399	1.47275
0.532803	1.472722
0.533207	1.472694
0.533612	1.472665
0.534017	1.472637
0.534422	1.472609
0.534828	1.472581
0.535234	1.472554
0.53564	1.472526
0.536046	1.472498
0.536453	1.47247
0.536861	1.472442
0.537268	1.472415
0.537676	1.472387
0.538084	1.47236
0.538492	1.472332
0.538901	1.472305
0.53931	1.472277
0.539719	1.47225
0.540129	1.472222
0.540539	1.472195
0.540949	1.472168
0.54136	1.472141
0.541771	1.472114
0.542182	1.472086
0.542593	1.472059
0.543005	1.472032
0.543417	1.472005
0.54383	1.471979
0.544242	1.471952
0.544656	1.471925
0.545069	1.471898
0.545483	1.471871
0.545897	1.471845
0.546311	1.471818
0.546726	1.471791
0.547141	1.471765
0.547556	1.471738
0.547971	1.471712
0.548387	1.471686
0.548804	1.471659
0.54922	1.471633
0.549637	1.471607
0.550054	1.47158
0.550472	1.471554
0.550889	1.471528
0.551307	1.471502
0.551726	1.471476
0.552145	1.47145
0.552564	1.471424
0.552983	1.471398
0.553403	1.471372
0.553823	1.471346
0.554243	1.47132
0.554664	1.471295
0.555085	1.471269
0.555506	1.471243
0.555928	1.471218
0.55635	1.471192
0.556772	1.471167
0.557195	1.471141
0.557617	1.471116
0.558041	1.47109
0.558464	1.471065
0.558888	1.47104
0.559312	1.471014
0.559737	1.470989
0.560162	1.470964
0.560587	1.470939
0.561012	1.470914
0.561438	1.470889
0.561864	1.470864
0.562291	1.470839
0.562717	1.470814
0.563144	1.470789
0.563572	1.470764
0.564	1.470739
0.564428	1.470715
0.564856	1.47069
0.565285	1.470665
0.565714	1.470641
0.566143	1.470616
0.566573	1.470591
0.567003	1.470567
0.567433	1.470542
0.567864	1.470518
0.568295	1.470494
0.568726	1.470469
0.569158	1.470445
0.56959	1.470421
0.570022	1.470397
0.570455	1.470372
0.570888	1.470348
0.571321	1.470324
0.571755	1.4703
0.572189	1.470276
0.572623	1.470252
0.573058	1.470228
0.573493	1.470204
0.573928	1.47018
0.574363	1.470157
0.574799	1.470133
0.575236	1.470109
0.575672	1.470085
0.576109	1.470062
0.576546	1.470038
0.576984	1.470015
0.577422	1.469991
0.57786	1.469968
0.578299	1.469944
0.578738	1.469921
0.579177	1.469897
0.579616	1.469874
0.580056	1.469851
0.580497	1.469828
0.580937	1.469804
0.581378	1.469781
0.581819	1.469758
0.582261	1.469735
0.582703	1.469712
0.583145	1.469689
0.583588	1.469666
0.584031	1.469643
0.584474	1.46962
0.584918	1.469597
0.585362	1.469574
0.585806	1.469552
0.58625	1.469529
0.586695	1.469506
0.587141	1.469484
0.587586	1.469461
0.588032	1.469438
0.588479	1.469416
0.588925	1.469393
0.589372	1.469371
0.58982	1.469348
0.590267	1.469326
0.590715	1.469304
0.591164	1.469281
0.591612	1.469259
0.592061	1.469237
0.592511	1.469215
0.59296	1.469192
0.59341	1.46917
0.593861	1.469148
0.594312	1.469126
0.594763	1.469104
0.595214	1.469082
0.595666	1.46906
0.596118	1.469038
0.59657	1.469016
0.597023	1.468994
0.597476	1.468973
0.59793	1.468951
0.598384	1.468929
0.598838	1.468907
0.599292	1.468886
0.599747	1.468864
0.600202	1.468843
0.600658	1.468821
0.601114	1.4688
0.60157	1.468778
0.602027	1.468757
0.602483	1.468735
0.602941	1.468714
0.603398	1.468692
0.603856	1.468671
0.604315	1.46865
0.604773	1.468629
0.605232	1.468608
0.605692	1.468586
0.606151	1.468565
0.606611	1.468544
0.607072	1.468523
0.607533	1.468502
0.607994	1.468481
0.608455	1.46846
0.608917	1.468439
0.609379	1.468418
0.609842	1.468398
0.610305	1.468377
0.610768	1.468356
0.611231	1.468335
0.611695	1.468315
0.612159	1.468294
0.612624	1.468273
0.613089	1.468253
0.613554	1.468232
0.61402	1.468212
0.614486	1.468191
0.614952	1.468171
0.615419	1.46815
0.615886	1.46813
0.616354	1.468109
0.616822	1.468089
0.61729	1.468069
0.617758	1.468049
0.618227	1.468028
0.618696	1.468008
0.619166	1.467988
0.619636	1.467968
0.620106	1.467948
0.620577	1.467928
0.621048	1.467908
0.621519	1.467888
0.621991	1.467868
0.622463	1.467848
0.622935	1.467828
0.623408	1.467808
0.623881	1.467788
0.624355	1.467769
0.624829	1.467749
0.625303	1.467729
0.625778	1.467709
0.626253	1.46769
0.626728	1.46767
0.627204	1.467651
0.62768	1.467631
0.628156	1.467612
0.628633	1.467592
0.62911	1.467573
0.629587	1.467553
0.630065	1.467534
0.630543	1.467514
0.631022	1.467495
0.631501	1.467476
0.63198	1.467457
0.63246	1.467437
0.63294	1.467418
0.63342	1.467399
0.633901	1.46738
0.634382	1.467361
0.634864	1.467342
0.635346	1.467323
0.635828	1.467304
0.63631	1.467285
0.636793	1.467266
0.637277	1.467247
0.63776	1.467228
0.638244	1.467209
0.638729	1.46719
0.639214	1.467171
0.639699	1.467153
0.640184	1.467134
0.64067	1.467115
0.641156	1.467097
0.641643	1.467078
0.64213	1.467059
0.642617	1.467041
0.643105	1.467022
0.643593	1.467004
0.644082	1.466985
0.64457	1.466967
0.64506	1.466948
0.645549	1.46693
0.646039	1.466912
0.64653	1.466893
0.64702	1.466875
0.647511	1.466857
0.648003	1.466839
0.648495	1.46682
0.648987	1.466802
0.649479	1.466784
0.649972	1.466766
0.650466	1.466748
0.650959	1.46673
0.651453	1.466712
0.651948	1.466694
0.652443	1.466676
0.652938	1.466658
0.653433	1.46664
0.653929	1.466622
0.654426	1.466604
0.654922	1.466586
0.65542	1.466569
0.655917	1.466551
0.656415	1.466533
0.656913	1.466516
0.657412	1.466498
0.657911	1.46648
0.65841	1.466463
0.65891	1.466445
0.65941	1.466427
0.65991	1.46641
0.660411	1.466392
0.660912	1.466375
0.661414	1.466358
0.661916	1.46634
0.662418	1.466323
0.662921	1.466305
0.663424	1.466288
0.663928	1.466271
0.664432	1.466254
0.664936	1.466236
0.665441	1.466219
0.665946	1.466202
0.666451	1.466185
0.666957	1.466168
0.667463	1.466151
0.66797	1.466134
0.668477	1.466116
0.668984	1.466099
0.669492	1.466083
0.67	1.466066

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: —

C₁₈H₃₄O₂ (Oleic acid): all datasets

About C18H34O2 (Oleic acid)

Oleic acid is a monounsaturated omega-9 fatty acid commonly found in various animal and vegetable fats and oils. It is a colorless or pale yellow liquid at room temperature with a mild odor and taste. Oleic acid is widely used in the manufacturing of soaps, detergents, and lotions, and serves as an emulsifying agent in the pharmaceutical industry. In materials science, it is often utilized as a surfactant and in the synthesis of nanoparticles due to its ability to stabilize particles in solution. Chemical formula: CH₃(CH₂)₇CH=CH(CH₂)₇COOH

More about C18H34O2 (Oleic acid) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/organic/C18H34O2 - oleic acid/nk/Jones.yml
ID: ds_4c228191f2a4
API: /v1/datasets/ds_4c228191f2a4

Plot