项目作者: SJ-Ang

项目描述 :
Tunneling Correction to Chemical Kinetics
高级语言: Python
项目地址: git://github.com/SJ-Ang/PyTUN.git
创建时间: 2017-05-29T10:01:20Z
项目社区:https://github.com/SJ-Ang/PyTUN

开源协议:GNU General Public License v3.0

下载


PyTUN

Tunneling Correction to Chemical Kinetics

Equations obtained from:

Wigner, E. Z., Über das Überschreiten von Potentialschwellen bei chemischen Reaktionen. 1932. Z. Phys. Chem. B, 19, 203. (Wigner’s approximation)

Garrett, B. C., & Truhlar, D. G., Semiclassical tunneling calculations. J. of Phys. Chem., 1979, 83(22), 2921-2926. (Eckart Potential)

R. T. Skodje, D. G. Truhlar and B. C. Garrett, A general small-curvature approximation for transition-state-theory transmission coefficients, J. Phys. Chem., 1981, 85, 3019–3023. (Parabolic Approximation)

Read Gaussian09 output files to generate Tunneling Correction κ (dimensionless), Corrected Rate kcorr (s-1) and Apparent Free Energy Barrier (kJmol-1)

Uncorrected rate [kuncorr] is obtained using the Eyring-Polanyi Equation, while Apparent Free Energy Barrier is back-transformed from the kcorr [kcorr=κkuncorr] using the same equation.

To evaluate κ for Eckart Potential, integration to obtain κ was calculated using 10-point Gauss-Legendre quadrature(Gives exact solution for polynomials of order up till 21)

Zero-point energy corrections are added to each species in the calculation.

User has to provide 6 files placed in the same directory as PyTUN.py:

  1. reactant.out (Frequency calculation of reactant)
  2. reactant_sp.out (Single-point calculation of reactant usually at a higher level of theory)
  3. product.out (Frequency calculation of product)
  4. product_sp.out (Single-point calculation of product)
  5. ts.out (Frequency calculation of transition state)
  6. ts_sp.out (Single-point calculation of transition state)

Run PyTUN with Python 2.7 (Python 3 is currently not supported)

Simply Type:

  1. python PyTUN.py

Sample Output:

  1. Uncorrected delta G dagger is 148.392236
  2. Uncorrected rate is 6.2526688665E-14
  3. The Wigner tunneling correction is 1.924509
  4. The Skodje tunneling correction is 3.328375
  5. The Eckart tunneling correction is 3.001622
  6. For Wigner Tunneling:
  7. Corrected rate is 1.2033316318E-13
  8. Apparent delta G dagger is 146.769335
  9. For Skodje Tunneling:
  10. Corrected rate is 2.0811226750E-13
  11. Apparent delta G dagger is 145.411330
  12. For Eckart Tunneling:
  13. Corrected rate is 1.8768150989E-13
  14. Apparent delta G dagger is 145.667483