1 / 5

Chemistry 6440 / 7440

Chemistry 6440 / 7440. Thermochemistry. Resources. McQuarrie, Statistical Thermodynamics, University Science Books, 1973 Foresman and Frisch, Exploring Chemistry with Electronic Structure Methods, Chapter 4 Cramer, Chapter 10 Jensen, Chapter 12 www.gaussian.com/thermo.html.

giona
Download Presentation

Chemistry 6440 / 7440

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chemistry 6440 / 7440 Thermochemistry

  2. Resources • McQuarrie, Statistical Thermodynamics, University Science Books, 1973 • Foresman and Frisch, Exploring Chemistry with Electronic Structure Methods, Chapter 4 • Cramer, Chapter 10 • Jensen, Chapter 12 • www.gaussian.com/thermo.html

  3. Thermodynamic Functions • U(T) - internal energy at absolute temperature T • H(T) = U(T) + PV = U(T) + RT - enthalpy • S(T) - entropy • G(T) = H(T) – T S(T) – free energy

  4. Thermodynamic Functions • at absolute zero, T = 0 U(0) = H(0) = G(0) U(0) = electronic energy + zero point energy S(0) = 0 for a pure crystalline substance (third law of thermodynamics)

  5. Thermodynamic Functions at T  0 • U(T) = U(0) + CvdT • heat at constant volume, molecule gains energy for translation (3/2 RT), rotation (3/2 RT) and vibration ( 1/(1-exp(-i/kT)) • H(T) = H(0) + CpdT • heat at constant pressure, molecule gains additional energy from expansion • S(T) > 0 • more states become accessible as the temperature increases

More Related