Refractive index of Phosphate Buffered Saline (PBS)

import lightsmith as ls

# Phosphate Buffered Saline (PBS): Janeiro et al. 2019: 10x solution; n 1.50–1.62 µm, k 1.15–1.80 µm
pbs = ls.fetch_refractiveindex("other", "PBS", "Janeiro", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(pbs.range_nm)  # (1500, 1620) nm
eps = pbs.eps([1560])  # complex permittivity

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_59f49a6f25a6/lightsmith"
pbs = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(pbs.source)  # citation and provenance travel with the data

# ... load pbs as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=pbs)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=1500, stop_nm=1620, num=81),
)
res = ls.solve(sim)  # exact Mie for a sphere
print(res.q_ext)     # extinction efficiency at each wavelength