At one wavelength

Refractive index n: 0.497421
Extinction coefficient k: 4.0489

Permittivity ε₁: -16.1462
Permittivity ε₂: 4.02802

Absorption coefficient α: 865895 cm⁻¹
Penetration depth δ = λ/(2πk): 23.0975 nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: -0.910279 µm⁻¹

Group index n_g: 1.0323
Group velocity dispersion: — fs²/mm

Dispersion parameter D: — 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

# Au (Gold): Werner et al. 2009: n,k 0.0176–2.48 µm
au = ls.fetch_refractiveindex("main", "Au", "Werner", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(au.range_nm)  # (17.586, 2479.68) nm
eps = au.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_62f0d6245c54/lightsmith"
au = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(au.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (au/werner-2009).

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

Comments and conditions

Experimental data: Derived from reflection electron energy-loss spectroscopy (REELS) spectra.

References

W. S. M. Werner, K. Glantschnig, C. Ambrosch-Draxl. Optical constants and inelastic electron-scattering data for 17 elemental metals, J. Phys Chem Ref. Data 38, 1013-1092 (2009)

doi:10.1063/1.3243762 Optical Constants and Inelastic Electron-Scattering Data for 17 Elemental Metals, Journal of Physical and Chemical Reference Data (2009)

Cite

Wolfgang S. M. Werner, Kathrin Glantschnig and Claudia Ambrosch-Draxl. Optical Constants and Inelastic Electron-Scattering Data for 17 Elemental Metals. Journal of Physical and Chemical Reference Data, 38, 1013-1092 (2009), doi:10.1063/1.3243762; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

150 rows as published

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

Au (Gold), Werner et al. 2009: n,k 0.0176–2.48 µm: n and k versus wavelength
λ (µm)	n	k
0.017586	0.8862	0.132
0.017712	0.8865	0.1337
0.017839	0.8868	0.1359
0.017969	0.8865	0.1376
0.0181	0.8869	0.1398
0.018233	0.8872	0.142
0.018368	0.8875	0.1437
0.018505	0.8878	0.1459
0.018644	0.8881	0.1475
0.018785	0.8885	0.1497
0.018929	0.8888	0.1513
0.019074	0.8891	0.1535
0.019222	0.8894	0.1552
0.019373	0.8897	0.1568
0.019525	0.89	0.1584
0.01968	0.8904	0.1606
0.019837	0.8907	0.1622
0.019997	0.8904	0.164
0.02016	0.8907	0.1656
0.020325	0.891	0.1672
0.020493	0.8914	0.1688
0.020664	0.8917	0.1705
0.020838	0.892	0.1721
0.021014	0.8917	0.1738
0.021194	0.892	0.1749
0.021377	0.8917	0.1766
0.021562	0.8915	0.1783
0.021752	0.8912	0.1795
0.021944	0.891	0.1813
0.02214	0.8907	0.1824
0.022339	0.8905	0.1842
0.022543	0.8897	0.186
0.022749	0.8894	0.1872
0.02296	0.8887	0.189
0.023175	0.8879	0.1909
0.023393	0.8867	0.1929
0.023616	0.8858	0.1942
0.023843	0.8846	0.1961
0.024075	0.8834	0.1987
0.024311	0.8822	0.2006
0.024551	0.8804	0.2027
0.024797	0.8787	0.2054
0.025047	0.8771	0.2081
0.025303	0.8755	0.2107
0.025564	0.8738	0.2134
0.02583	0.8718	0.2168
0.026102	0.8698	0.2202
0.02638	0.8673	0.2242
0.026663	0.8655	0.2282
0.026953	0.8631	0.2323
0.027249	0.8614	0.2368
0.027552	0.8594	0.242
0.027862	0.8574	0.2473
0.028178	0.8556	0.253
0.028502	0.8545	0.2592
0.028834	0.8535	0.2654
0.029173	0.8525	0.2716
0.02952	0.8523	0.2781
0.029876	0.8521	0.2846
0.03024	0.8531	0.2913
0.030613	0.8536	0.2976
0.030996	0.855	0.3035
0.031388	0.8566	0.3094
0.031791	0.8583	0.314
0.032204	0.8598	0.3181
0.032627	0.8606	0.3219
0.033062	0.8607	0.3253
0.033509	0.8602	0.3284
0.033968	0.8584	0.3314
0.03444	0.8551	0.335
0.034925	0.8509	0.3391
0.035424	0.8458	0.3441
0.035937	0.8394	0.3502
0.036466	0.832	0.3582
0.03701	0.8233	0.3686
0.037571	0.8147	0.3817
0.038149	0.8067	0.3985
0.038745	0.7992	0.4192
0.03936	0.7946	0.4443
0.039995	0.7952	0.4747
0.040651	0.8046	0.5083
0.041328	0.8268	0.5418
0.042029	0.8634	0.5652
0.042753	0.9062	0.5694
0.043503	0.9419	0.5515
0.04428	0.9581	0.5224
0.045085	0.9541	0.4952
0.04592	0.9375	0.4784
0.046786	0.9149	0.4722
0.047686	0.8906	0.4755
0.048621	0.8667	0.4869
0.049594	0.8434	0.5063
0.050606	0.8224	0.5314
0.05166	0.8032	0.564
0.052759	0.7877	0.6037
0.053906	0.7771	0.6518
0.055104	0.774	0.7086
0.056356	0.783	0.7753
0.057667	0.8119	0.8504
0.05904	0.8715	0.926
0.06048	0.9706	0.9808
0.061992	1.0948	0.9791
0.063582	1.1896	0.9095
0.065255	1.2164	0.8196
0.067018	1.1943	0.7565
0.06888	1.1566	0.7293
0.070848	1.121	0.7284
0.072932	1.0932	0.7437
0.075142	1.0748	0.7695
0.07749	1.0652	0.8004
0.07999	1.0634	0.8341
0.082656	1.0678	0.8691
0.085506	1.0781	0.903
0.08856	1.0926	0.9358
0.09184	1.1096	0.9666
0.095372	1.1287	0.995
0.099187	1.1474	1.0215
0.10332	1.1642	1.0466
0.107812	1.178	1.0722
0.112713	1.1875	1.101
0.11808	1.1929	1.1363
0.123984	1.1961	1.1822
0.13051	1.202	1.2429
0.13776	1.2191	1.3203
0.145864	1.2599	1.4097
0.15498	1.3358	1.4938
0.165312	1.4391	1.5388
0.17712	1.5217	1.5213
0.190745	1.519	1.4796
0.20664	1.4222	1.5019
0.225426	1.2959	1.6633
0.247968	1.2591	1.9812
0.261019	1.3211	2.1777
0.27552	1.4641	2.3629
0.291728	1.6918	2.4761
0.30996	1.9442	2.436
0.330625	2.0725	2.2335
0.354241	1.9648	2.0061
0.38149	1.6513	1.9194
0.413281	1.2446	2.0722
0.450852	0.8906	2.4674
0.495937	0.6607	3.0134
0.551041	0.5307	3.6538
0.619921	0.468	4.3982
0.708481	0.4576	5.2933
0.826561	0.5009	6.4242
0.991874	0.6201	7.9404
1.239842	0.8792	10.1331
1.653123	1.4692	13.659
2.479684	3.1274	20.3613

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: —

Plot