Reflectance spectroscopy, photoelastically modulated

Stacchiola D, Thompson A, Kaltchev G, Tysoe WT (2002) Photoelastic modulation-reflection absorption infrared spectroscopy of CO on Pd(lll). J Vac Sci Technol A 20 2101... 

Polarization-modulation infrared reflection-absorption spectroscopy (PM-IR-RAS) spectra were recorded with a Bruker ITS 66/S Fourier transform infrared spectrometer equipped with a PMA 37 polarization modulation module and a ititrogen-cooled MCT detector. The infrared beam was first p-polarized with a ZnSe wire grid polarizer (Specac) before passing through a photoelastic modulator (Hinds Instruments, PEM-90), which modulated at a frequency of 74 kHz. A lock-in ampHfier (Stanford model SR-830) was used to obtain the PM-IRRAS spectra. The half-wave retardation frequency was set at 4000 cm . The PM-IR-RAS spectra were recorded as S= R -Rs)/(R +Rg). A total of 250 scans at a resolution of 4 cm were collected for each measurement at an angle of incidence of 82.5° with respect to the normal to the sample surface. 

Infrared Spectroscopy. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) data were collected using a Nicolet MAGNA-IR 860 Fourier transform spectrometer equipped with a liquid nitrogen-cooled mercury-cadmium-telluride (MCT) detector and a Hinds Instruments PEM-90 photoelastic modulator. The p-polarized light was incident at 80° from the surface normal. The spectra were collected for 1000 scans at a spectral resolution of 4 cm . ... 

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