BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Efficient calculation of the absolute molecular entropy with DFT a
 nd extended tight-binding methods - Dr Philipp Pracht\, Cambridge
DTSTART:20230130T143000Z
DTEND:20230130T150000Z
UID:TALK196315@talks.cam.ac.uk
CONTACT:Dr Christoph Schran
DESCRIPTION:The realistic modelling of chemical reactions at finite temper
 atures is one main goal for computational chemistry\, where a primary task
  lies in accurately calculating free energies. Setting aside the issue of 
 solvation and referring to calculations for the isolated molecule\,\nthe l
 atter is essentially a problem of efficient computation of molecular entro
 py. In this talk\,\nI present an automated composite scheme for the accura
 te and numerically stable calculation of molecular entropy by efficiently 
 combining DFT and semi-empirical extended\ntight-binding (xTB) methods.[1\
 ,2] Anharmonic effects are included through a modified rigid-rotor-harmoni
 c-oscillator approximation and the Gibbs–Shannon entropy[3] for extensiv
 e conformational ensembles\, which are generated by a specialized meta-dyn
 amics[4] sampling procedure and extrapolated to completeness. I will demon
 strate the approach on an established benchmark set\, where unprecedented 
 root mean square deviations\, far better than chemical accuracy\, are achi
 eved. Furthermore\, I will address possible extensions to the workflow and
  mention effects due to the choice of the underlying potential or the envi
 ronment\, for example\, by implicit solvation.[5]\n\n[1] C. Bannwarth\, S.
  Grimme\, et al.\, WIREs Comput Mol Sci.\, 2021\, 11\, e1493.\n\n[2] P. Pr
 acht\, S. Grimme\, Chem. Sci.\, 2021\, 12\, 6551–6568\n\n[3] D. Suárez\
 , N. Dı́az\, WIREs Comput. Mol. Sci.\, 2015\, 5\, 1--26.\n\n[4] P. Prach
 t\, F. Bohle\, S. Grimme\, PCCP\, 2020\, 22\, 7169--7192\n\n[5] J. Gorges\
 , S. Grimme\, A. Hansen\, P. Pracht\, PCCP\, 2022\, 24\, 12249-12259.
LOCATION:Mott Seminar Room 531\, Cavendish Laboratory
END:VEVENT
END:VCALENDAR