The design and construction of a microspectrophotometer

A nonrecording spectrophotometer has been constructed to measure spectra of orientated single crystals using polarized light (5 to 50 kK). The high extinction coefficients encountered in transition metal complexes necessitated the ability to measure absorbance values as high as 4.0. This has been achieved by the use of a double prism monochromator to reduce stray light and by attenuation of the reference beam to hold the signal to reference voltage ratio at not less than 1 to 100. The sources of error in measurements on crystalline samples are discussed; the effects of eccentricity in the polarizing prism and the use of microscope objectives giving a nonparallel light beam at the sample are considered in detail.