Fast and artifact-free circular dichroism measurement of solid-state structural changes

A novel chiroptical spectrophotometer, Multichannel (MC)-circular dichroism (CD), which does not require a wavelength scan and provides artifact-free CD spectra in seconds, was developed by solving the incompatibility problem between data acquisition and modulation timescales. The design and instrumentation are compared with the Universal Chiroptical Spectrophotometer (UCS)-1, which can measure artifact-free CD spectra in the solid state. Enantiomeric single crystals composed of achiral components, α-Ni(H₂ O)₆ ・SO₄ , and achiral films with substantial macroscopic anisotropies were measured on both MC-CD and UCS-1 and compared.