I’m trying to carry out an abstraction reaction in my system (bimolecular reaction) to get the branching ratios and abstraction rate constant but after writing the code using help from mesmer I can’t see any branching ratio in my results. Also the mole fraction is not available. Attached is the code
Thank-you for sending me your input. I have taken a look and I see that it is for a set of bimolecular reactions only. This is not the sort of system that MESMER was designed to model, MESMER was designed to mode systems with multiple energy wells. The reactions in your input will have no pressure dependence which is a key feature of the systems that MESMER is designed to model. However, I have run your input through MESMER and I do get what appear to be sensible results: the branching ratios are the final populations of each of the species, which can be viewed by loading the MESMER output file into FireFox as described in the manual, or by looking a tthe results in the .log file. For the case of 298 K the branching rations are A1: 3.17703e-05, A2: 0.00010777, and A3: 0.99986, which are consistent with the activation barrier heights. Even so, I think these estimates will be quite crude, because the reactions involve the transfer of an H-atom so quantum mechanical tunnelling should be taken into account. This can be done in MESMER but for the most accurate results I think that one would have to account for small curvature tunnelling and so perhaps a code like POLYRATE is more appropriate.
I hope this helps a little.
With regards, Struan
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Hi Struanr,
I’m trying to carry out an abstraction reaction in my system (bimolecular reaction) to get the branching ratios and abstraction rate constant but after writing the code using help from mesmer I can’t see any branching ratio in my results. Also the mole fraction is not available. Attached is the code
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Hello,
Thank-you for sending me your input. I have taken a look and I see that it is for a set of bimolecular reactions only. This is not the sort of system that MESMER was designed to model, MESMER was designed to mode systems with multiple energy wells. The reactions in your input will have no pressure dependence which is a key feature of the systems that MESMER is designed to model. However, I have run your input through MESMER and I do get what appear to be sensible results: the branching ratios are the final populations of each of the species, which can be viewed by loading the MESMER output file into FireFox as described in the manual, or by looking a tthe results in the .log file. For the case of 298 K the branching rations are A1: 3.17703e-05, A2: 0.00010777, and A3: 0.99986, which are consistent with the activation barrier heights. Even so, I think these estimates will be quite crude, because the reactions involve the transfer of an H-atom so quantum mechanical tunnelling should be taken into account. This can be done in MESMER but for the most accurate results I think that one would have to account for small curvature tunnelling and so perhaps a code like POLYRATE is more appropriate.
I hope this helps a little.
With regards, Struan
Thank you Struan for your help