ePubs
The open archive for STFC research publications
Home
About ePubs
Content Policies
News
Help
Privacy/Cookies
Suggest an Enhancement
Contact ePubs
Full Record Details
Persistent URL
http://purl.org/net/epubs/work/64409
Record Status
Checked
Record Id
64409
Title
Proton vibrational dynamics in lithium imide investigated through incoherent inelastic and Compton neutron scattering
Contributors
A Pietropaolo (Università degli Studi di Milano-Bicocca)
,
D Colognesi (Istituto dei Sistemi Complessi)
,
M Catti (Università degli Studi di Milano-Bicocca)
,
A-C Nale (Università degli Studi di Milano-Bicocca)
,
MA Adams (STFC Rutherford Appleton Lab.)
,
AJ Ramirez-Cuesta (STFC Rutherford Appleton Lab.)
,
J Mayers (STFC Rutherford Appleton Lab.)
Abstract
In the present study we report neutron spectroscopic measurements on polycrystalline lithium imide, namely, incoherent inelastic neutron scattering at 20 K, and neutron Compton scattering from 10 K up to room temperature. From the former technique the H-projected density of phonon states up to 100 meV is derived, while the latter works out the spherically averaged single-particle (i.e., H, Li, and N) momentum distributions and, from this, the mean kinetic energies. Only for H at the lowest investigated temperature, non-Gaussian components of its momentum distribution are detected. However, these components do not seem directly connected to the system anharmonicity, being fully compatible with the simple N-H bond anisotropy. Neutron data are also complemented by ab initio lattice dynamics simulations, both harmonic and, at room temperature, carried out in the framework of the so-called "quantum colored noise thermostat" method. The single-particle mean kinetic energies in lithium imide as a function of temperature show a quite peculiar behavior at the moment not reproduced by ab initio lattice dynamics methods, at least as far as H and Li are concerned. As matter of fact, neither their low temperature values nor their temperature trends can be precisely explained in terms of standard phonon calculations.
Organisation
ISIS
,
ISIS-TOSCA
,
ISIS-VESUVIO
,
STFC
Keywords
Funding Information
Related Research Object(s):
Licence Information:
Language
English (EN)
Type
Details
URI(s)
Local file(s)
Year
Journal Article
J Chem Phys
137, no. 20 (2012): 204309.
doi:10.1063/1.4767566
2012
Showing record 1 of 1
Recent Additions
Browse Organisations
Browse Journals/Series
Login to add & manage publications and access information for OA publishing
Username:
Password:
Useful Links
Chadwick & RAL Libraries
SHERPA FACT
SHERPA RoMEO
SHERPA JULIET
Journal Checker Tool
Google Scholar