12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

The electric field gradient in mercuric chloride

15 Jul 2011, 09:15
15m
Parthenon

Parthenon

Oral Presentation Track A - Condensed Matter Physics and Material Science CMPMS1

Speaker

Dr Jonathan Keartland (University of the Witwatersrand)

Description

The temperature dependence of the 35Cl quadrupolar resonance frequency has been measured in a high purity sample of mercuric chloride (HgCl2) over the temperature range 4 K - 460 K. The results allow the temperature dependence of the electric field gradient (efg) at the two inequivalent sites of the chlorine atoms to be determined. Several models were considered to describe the experimental observations, including both librational and vibrational modes. The Bayer model for librational modes provides a satisfactory description of the changes in the efg over the entire temperature range, when the temperature variation of the lattice modes is taken into account, while the other mechanisms considered provide less convincing descriptions. A single librational mode with a wavenumber of approximately 26 cm-1 can account for the variation of the electric field gradient over the temperature range investigated. Our conclusions are consistent with the results of optical spectroscopy investigations.

Level (Hons, MSc, <br> &nbsp; PhD, other)? other
Consider for a student <br> &nbsp; award (Yes / No)? No
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? Yes

Primary author

Dr Jonathan Keartland (University of the Witwatersrand)

Presentation Materials