Refractive index of CsBr (Cesium bromide)

import lightsmith as ls

# CsBr (Cesium bromide): Rodney and Spindler 1953: n 0.365–39 µm; 27 °C
csbr = ls.fetch_refractiveindex("main", "CsBr", "Rodney", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(csbr.range_nm)  # (365, 39000) nm
eps = csbr.eps([633])  # complex permittivity

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_51a710a88bab/lightsmith"
csbr = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(csbr.source)  # citation and provenance travel with the data

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

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_51a710a88bab/lightsmith?model=drude_lorentz"
csbr_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))