The high energy-transfer region in neutron scattering vibrational spectra: What does it mean and what could it be useful for?

Article type: Research Article

Authors: Colognesi, Daniele

Affiliations: Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, Via Madonna del Piano 10, 50019, Sesto Fiorentino (FI), Italy. E-mail: daniele.colognesi@fi.isc.cnr.it

Abstract: We analyze the high energy transfer part of a neutron scattering spectrum from a protonated molecular crystal measured on an inverse-geometry crystal-analyzer spectrometers like TOSCA or VISION. In spite of the little information available in this range, we show that it is possible to exploit it in order to perform a new normalization procedure. Then a simple free gas model based on the impulse approximation is presented, followed by approximate methods for quickly correcting experimental data for the main unwanted effects. At the end, a practical example based on solid urea data is presented and the new normalization procedure is tested comparing the results from two different scattering laws (one being the free gas model). The two normalization constants obtained turn out to be practically identical showing the reliability of the suggested approach.

Keywords: Inelastic neutron scattering, vibrational spectroscopy

DOI: 10.3233/JNR-170053

Journal: Journal of Neutron Research, vol. 19, no. 3-4, pp. 147-167, 2017