Institutional Research Information Service
UCL Logo
Please report any queries concerning the funding data grouped in the sections named "Externally Awarded" or "Internally Disbursed" (shown on the profile page) to your Research Finance Administrator. Your can find your Research Finance Administrator at https://www.ucl.ac.uk/finance/research/rs-contacts.php by entering your department
Please report any queries concerning the student data shown on the profile page to:

Email: portico-services@ucl.ac.uk

Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
Publication Detail
Polyamorphic amorphous silicon at high pressure: raman and spatially resolved X-ray scattering and molecular dynamics studies.
We studied the low-frequency Raman and X-ray scattering behavior of amorphous silicon (a-Si) at high pressure throughout the range where the density-driven polyamorphic transformation between the low-density amorphous (LDA) semiconductor and a novel metallic high-density amorphous (HDA) polyamorph occurs. The experimental data were analyzed with the aid of molecular dynamics (MD) simulations using the Stillinger-Weber potential. The heat capacity of a-Si obtained from the low pressure Raman data exhibits non Debye-like behavior, but the effect is small, and our data support the conclusion that no boson peak is present. The high-pressure Raman data show the presence of a distinct low frequency band for the HDA polyamorph in agreement with ab initio MD simulations. Spatially resolved synchrotron X-ray diffraction was used to study the high pressure behavior of the a-Si sample throughout the LDA-HDA transition range without interference by crystallization events. The X-ray data were analyzed using an iterative refinement strategy to extract real-space structural information. The appearance of the first diffraction peak (FDP) in the scattering function S(Q) is discussed in terms of the void structure determined from Voronoi analysis of the MD simulation data.
Publication data is maintained in RPS. Visit https://rps.ucl.ac.uk
 More search options
UCL Researchers
Dept of Chemistry
Dept of Chemistry
University College London - Gower Street - London - WC1E 6BT Tel:+44 (0)20 7679 2000

© UCL 1999–2011

Search by