University of MichiganAnn Arbor, MI 48109-2143

Climate and Space Sciences and Engineering

MultiWell Program Suite

J. R. Barker, T. L. Nguyen, J. F. Stanton, C. Aieta, M. Ceotto,
F. Gabas, T. J. D. Kumar, C. G. L. Li, L. L. Lohr, A. Maranzana,
N. F. Ortiz, J. M. Preses, J. M. Simmie, J. A. Sonk, and P. J. Stimac


This is the MultiWell web site. Contact John R. Barker at for further information or to be added to the email list.

NEW IN VERSION 2020 (Feb 2020)

1. ktools: The output data generated by this code has not changed, but the code has been enhanced considerably:

  • A compiled Windows executable is now available.
  • Up to 20 comment lines (each preceded by "!") can be added after the title line.
  • The meaning of the key word 'whatdo' has been changed. When it is set to "savefiles", all of the 1D (i.e. J-summed) and 2D output files are saved. These files are typically very large, consuming large amounts of disk space. If they are not needed, such as when only the canonical (high pressure limit) rate constants are desired, the key word can be any other word (e.g. "nosavefiles") and the large files will not be saved.
  • A backup file for the input is saved every time the code is run.
  • The maximum number of energy grains is limited only by the available computer memory (although execution speed will become very slow for extremely large calculations).
  • If the maximum number of rotational states selected by the user is not large enough, execution will be terminated and an error message will give further guidance.
  • If the maximum number of rotational states selected by the user exceeds the intrinsic limit where the effective potential of the reactant, Veff(reactant), is ≥ Veff(TTS) for all of the trial transition states, the output is automatically limited to the intrinsic limit.
  • The numbers of energy grains, rotational states, and the intrinsic limit are now reported along with the canonical rate constants in the output file with suffix ".canonical".

2. "box" type of separable degree of freedom: This "particle-in-a-box" d.o.f. can be optionally selected by the User and is not used very often. It came to our attention that the subroutine for this degree of freedom was broken and had been broken for some time. It has now been fixed. It is used by densum, bdens, paradensum, sctst, and parsctst. Because this option is not selected very often and because use of the broken subroutine generated a fatal error, the problem was not likely to have impacted previous calculations.

3. multiwell: Estart.f, the subroutine that defines the initial energy distribution for master equation simulations, was modified slightly to improve performance at temperatures below 100 K. This revision has essentially no impact at higher temperatures.

4. multiwell: improvement: The default maximum numbers of Wells, Product Sets, reaction channels from each well were increased to 70, 60, and 60, respectively.

5. multiwell: revision:  The logarithmic time user option (keyword "LOGT") has been revised to start output at 1.e-16 s (formerly 1.e-18 s). This revision was made because the extent of reaction is essentially negligible prior to 1.e-16 s. This revision affects only the output files and is expected to have very little impact on users.

6. thermo: improvement: The output was modified slightly by increasing the number of significant digits reported for that Arrhenius parameter "B". This improvement will give better accuracy when the magnitude of parameter B is small.

7. thermo: bug fix: The option to choose wavenumber units for enthalpy (key word "CM-1") was broken and has been fixed. This revision had no impact, because the option didn't work and users had alternative choices (i.e. kcal/mol or kJ/mol).

8. TS: maintenance revisions: Both the code and the TS User Manual have been revised in a number of ways to fix minor bugs and to make some improvements.