Soret Band

Related terms

Chromophore

The molecular subunit responsible for a dye's colour, typically a conjugated double-bond system; chemical erasure destroys the chromophore while leaving the decolourised...

Ionising Radiation

Electromagnetic radiation whose photon energy exceeds the ionisation potential of atoms (typically above ~10 eV); includes gamma rays and X-rays. UV below...

Mid-Infrared (Mid-IR)

The 2500-25000 nm (400-4000 cm^-1) spectral region where functional-group vibrational absorptions serve as chemical fingerprints; the operating region of FTIR spectroscopy.

Photon

A quantum of electromagnetic radiation; a discrete energy packet with energy E = hν where h is Planck's constant and ν is...

Photon Energy (eV)

Photon energy expressed in electron volts; UV photons carry 3-12 eV (chemically reactive), visible 1.8-3.1 eV, mid-IR 0.05-0.5 eV (vibrational excitation only).

Planck-Einstein Equation

E = hν = hc/λ; relates photon energy to frequency and wavelength. Foundation of all spectral energy calculations.

Refractive Index

A physical property of glass (and other transparent materials) that describes how much light bends when passing through it. Forensic glass comparison...

UV-a

The ultraviolet band from 315 to 400 nm; the primary band used for UV-reflectance forensic imaging of bruises, GSR, and bite marks...

UV-C

Ultraviolet radiation in the 100-280 nm band; the 254 nm germicidal line excites biological-fluid fluorescence in forensic screening.

Wave-Particle Duality

The quantum-mechanical property of electromagnetic radiation: it behaves as a wave (diffraction, interference, polarisation) and as a stream of photons (photoelectric effect,...

Wavenumber (Cm^-1)

Reciprocal of wavelength in centimetres, the standard unit for mid-infrared spectra; 1 cm^-1 = 10^7 / λ(nm).

Explained in

• Light, Photons and the Forensic EM SpectrumThe intense porphyrin absorption band of haemoglobin at 415 nm; the spectral basis for bloodstain contrast enhancement.