Diamond atr

The FTIR-ATR spectroscopy was performed in a Bruker Tensor II FT-IR with a Diamond ATR (Bruker Optics, Ettinger, Germany) and a liquid N₂-cooled photovoltaic MCT detector. Briefly, 20 mg/mL samples at room temperature (RT) were used for the analysis and 64 scans with a resolution of 4 cm⁻¹ against the background subtraction were assessed. The FTIR-ATR spectra were corrected for baseline and then analysed using OPUS 7.5 Software (Bruker Optics, Ettlingen, Germany).

INS spectra were recorded with the high resolution, broad band spectrometer TOSCA⁵⁸ at the ISIS Pulsed Neutron and Muon Facility⁵⁹ . The samples, ~ 2 g, were loaded into indium sealed aluminium cans, cooled to < 20 K and measured for 1–2 h. The spectra are available at the INS database: http://wwwisis2.isis.rl.ac.uk/INSdatabase/. Infrared spectra were recorded at room temperature using a Bruker Vertex70 FTIR spectrometer, over the range 100–4000 cm⁻¹ at 4 cm⁻¹ resolution with a DLaTGS detector using 64 scans and the Bruker Diamond ATR. FT-Raman spectra were recorded with a Bruker MultiRam spectrometer using 1064 nm excitation, 4 cm⁻¹ resolution, 500 mW laser power and 64 scans at room temperature.

The INS spectrum was recorded at less than 20 K using TOSCA [15 (link)] at ISIS (http://www.isis.stfc.ac.uk/). The spectrum is available at the INS database: http://wwwisis2.isis.rl.ac.uk/INSdatabase/. Infrared spectra were recorded using a Bruker Vertex70 FTIR spectrometer, over the range of 100–4000 cm⁻¹ at 4 cm⁻¹ resolution with a DLaTGS detector using 64 scans and the Bruker Diamond ATR. The use of the ultra-wide range beamsplitter enabled the entire spectral range to be recorded without the need to change beamsplitters. Variable temperature ATR infrared spectra (150–300 K) were recorded using a Specac Golden Gate accessory. The spectra have been corrected for the wavelength-dependent variation in path length using the Bruker software and also baseline corrected. FT-Raman spectra were recorded with a Bruker MultiRam spectrometer using 1064 nm excitation, 4 cm⁻¹ resolution, 500 mW laser power and 64 scans. The liquid MSA Raman spectrum was measured in air at room temperature in a quartz cuvette; the solid MSA Raman spectrum was obtained by cooling the filled cuvette in liquid N₂.