BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Bending modes\, elastic constants and mechanical stability of grap
 hitic systems - Gianluca Savini (University of Sussex)
DTSTART:20081119T120000Z
DTEND:20081119T122000Z
UID:TALK14989@talks.cam.ac.uk
CONTACT:Neil Drummond
DESCRIPTION:The thermodynamic and mechanical properties of graphitic syste
 ms are strongly dependent on \nthe shear elastic constant C44. Our density
  functional calculations provide the first complete determination of thei
 r elastic constants and exfoliation energies. We show that stacking misori
 entation leads to a severe lowering of C44 from 4.5GPa (perfect stacking) 
 to 0.24±0.06 GPa (random stacking). The lower exfoliation energy and the 
 lower C44 (more bending modes) suggest that flakes with random stacking s
 hould be easier to exfoliate than the ones with perfect or rhombohedral st
 acking in agreement with a recent experiment [Y. Hernandez _et al_.\, Natu
 re Nanotech. *3*\, 563(2008)].\n\n"Download slides":http://www.tcm.phy.cam
 .ac.uk/~ndd21/ESDG_slides/savini191108.pdf (PDF)
LOCATION:TCM Seminar Room\, Cavendish Laboratory
END:VEVENT
END:VCALENDAR