A wide-range Raman shift wave-number measure based on a polymeric material
摘要
The Raman-shift wave number is one of the most important parameters in the Raman spectroscopy. Since the accuracy of finding the Raman-shift wave number strongly depends on the technical characteristics of the Raman spectrometers and the conditions of measurements, physically and chemically stable easy-to-use reference materials, e.g., solid-state materials, are required to calibrate these devices on the wave-number scale. A Raman-shift wave-number measure is developed and tested for the purposes of approving the type of measuring instruments. This measure is intended for the purposes of calibration and verification of measuring device on the scale of wave-numbers of Raman shifts. The measure has the form of a polymeric film made of polystyrene and sulfur and placed in a special mandrel. The material of the measure is in the solid aggregate state. The metrological characteristics of the developed measure are investigated. It is shown that the measure makes it possible to store and transmit the unit of Raman-shift wave numbers for the wavelengths of Raman scattering excitation equal to 532–785 nm within the range 80–3000 cm–1 with an error of at most 1 cm–1. The traceability to the State Primary Special Standard GÉT 187-2016 of the units of energy, energy-density distribution, pulse duration, and the wavelength of laser radiation and to the State Working Standard of the unit of wavelength for fiber-optic data-transmission systems within the range of values 0.4–3.4 μm (3.1.ZZA.0114.2018) is guaranteed. The superposition of the polystyrene and sulfur lines in the Raman spectrum of the developed measure makes it possible to expand the range of wave-numbers of the Raman shifts (as compared with the range of similar solid-state measures of foreign production), especially in the short-wave region.