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What does the positive and negative adsorption energy indicates?...
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+ Adsorption
+ Interpretation
+ Discrete fourier transform
+ Gaussian (software)
+ Density functional theory
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Leo Roos
What does the positive and negative adsorption energy indicates?...
Eadsorption = - = Attraction (Adsorption) Eadsorption = + = Repulsion (No Adsorption) To interpret the results of adsorption, how interactions should be evaluated and you can use different analyzes to interpret interactions and, validate absorption results obtained from quantum computing. For example; NCI analysis (Non-Covalent Interactions is a visualization index based on the density an identification of non-covalent interactions). SAPT analysis (Symmetry-adapted perturbation theory provides a means of directly computing the non-covalent interaction between two molecules, that is, the interaction energy is determined without computing the total energy. Also, SAPT provides a decomposition of the interaction energy into physically components: electrostatic, exchange, induction, and dispersion terms). And etc...
Eadsorption = - = Attraction (Adsorption) Eadsorption = + = Repulsion (No Adsorption) To interpret the results of adsorption, how interactions should be evaluated and you can use different analyzes to interpret interactions and, validate absorption results obtained from quantum computing. For example; NCI analysis (Non-Covalent Interactions is a visualization index based on the density an identification of non-covalent interactions). SAPT analysis (Symmetry-adapted perturbation theory provides a means of directly computing the non-covalent interaction between two molecules, that is, the interaction energy is determined without computing the total energy. Also, SAPT provides a decomposition of the interaction energy into physically components: electrostatic, exchange, induction, and dispersion terms). And etc...
Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption). Rate of adsorption decreases with increasing temperature.
Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption). Rate of adsorption decreases with increasing temperature.
Amarjyoti Das , as already replied earlier the negative and postive adsorption energy directs us for exothermic and endothermic reactions respectively which decide the feasibility of the reaction to occur or not. Although, on the basis of Eads we cannot conclude whether the reaction will take place or not. Since the surface of any nanosheet is not uniform in terms of charge density and there are activated sites for different gas molecules based on their electrophilic and eletrophobic nature, therefore adsorption energy of a Molecule could be negative on a specific site but could be positive for another site. Thus different adsorption sites for different gas molecules should be checked, while we have also seen the orientation of the molecule determine the Hydrogen bonding between the adsorbate-adsorbent pair hence governing the Eads. Thus, I would suggest that for gas adsorption, you should not rely only on the Eads but should also take other parameters into account.
Amarjyoti Das , as already replied earlier the negative and postive adsorption energy directs us for exothermic and endothermic reactions respectively which decide the feasibility of the reaction to occur or not. Although, on the basis of Eads we cannot conclude whether the reaction will take place or not. Since the surface of any nanosheet is not uniform in terms of charge density and there are activated sites for different gas molecules based on their electrophilic and eletrophobic nature, therefore adsorption energy of a Molecule could be negative on a specific site but could be positive for another site. Thus different adsorption sites for different gas molecules should be checked, while we have also seen the orientation of the molecule determine the Hydrogen bonding between the adsorbate-adsorbent pair hence governing the Eads. Thus, I would suggest that for gas adsorption, you should not rely only on the Eads but should also take other parameters into account.
For endothermic adsorption, it is a case of activated adsorption. I would like to suggest to search transition state.
Activated / Barrierless Adsorption question is described in our article by Stanislav K. Ignatov, Andrey I. Okhapkin, Oleg B. Gadzhiev, Alexey G. Razuvaev, Sebastian Kunz, and Marcus Bäumer, Adsorption and Diffusion of Hydrogen on the Surface of the Pt24 Subnanoparticle. A DFT Study, J. Phys. Chem. C, 2016, 120 (33), pp 18570–18587 http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04555 I hope, it is helpful. If it is helpful and/or instructive, I would like to ask you to cite it in an appropriate context.
For endothermic adsorption, it is a case of activated adsorption. I would like to suggest to search transition state.
Activated / Barrierless Adsorption question is described in our article by Stanislav K. Ignatov, Andrey I. Okhapkin, Oleg B. Gadzhiev, Alexey G. Razuvaev, Sebastian Kunz, and Marcus Bäumer, Adsorption and Diffusion of Hydrogen on the Surface of the Pt24 Subnanoparticle. A DFT Study, J. Phys. Chem. C, 2016, 120 (33), pp 18570–18587 http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04555 I hope, it is helpful. If it is helpful and/or instructive, I would like to ask you to cite it in an appropriate context.
As suggested by Mutee Ur Rehman , Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption).
As suggested by Mutee Ur Rehman , Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption).
Eadsorption = - = Attraction (Adsorption)
Eadsorption = + = Repulsion (No Adsorption)
To interpret the results of adsorption, how interactions should be evaluated and you can use different analyzes to interpret interactions and, validate absorption results obtained from quantum computing.
For example;
NCI analysis (Non-Covalent Interactions is a visualization index based on the density an identification of non-covalent interactions).
SAPT analysis (Symmetry-adapted perturbation theory provides a means of directly computing the non-covalent interaction between two molecules, that is, the interaction energy is determined without computing the total energy. Also, SAPT provides a decomposition of the interaction energy into physically components: electrostatic, exchange, induction, and dispersion terms).
And etc...
Eadsorption = - = Attraction (Adsorption)
Eadsorption = + = Repulsion (No Adsorption)
To interpret the results of adsorption, how interactions should be evaluated and you can use different analyzes to interpret interactions and, validate absorption results obtained from quantum computing.
For example;
NCI analysis (Non-Covalent Interactions is a visualization index based on the density an identification of non-covalent interactions).
SAPT analysis (Symmetry-adapted perturbation theory provides a means of directly computing the non-covalent interaction between two molecules, that is, the interaction energy is determined without computing the total energy. Also, SAPT provides a decomposition of the interaction energy into physically components: electrostatic, exchange, induction, and dispersion terms).
And etc...
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Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption). Rate of adsorption decreases with increasing temperature.
Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption). Rate of adsorption decreases with increasing temperature.
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Amarjyoti Das , as already replied earlier the negative and postive adsorption energy directs us for exothermic and endothermic reactions respectively which decide the feasibility of the reaction to occur or not. Although, on the basis of Eads we cannot conclude whether the reaction will take place or not. Since the surface of any nanosheet is not uniform in terms of charge density and there are activated sites for different gas molecules based on their electrophilic and eletrophobic nature, therefore adsorption energy of a Molecule could be negative on a specific site but could be positive for another site. Thus different adsorption sites for different gas molecules should be checked, while we have also seen the orientation of the molecule determine the Hydrogen bonding between the adsorbate-adsorbent pair hence governing the Eads. Thus, I would suggest that for gas adsorption, you should not rely only on the Eads but should also take other parameters into account.
Amarjyoti Das , as already replied earlier the negative and postive adsorption energy directs us for exothermic and endothermic reactions respectively which decide the feasibility of the reaction to occur or not. Although, on the basis of Eads we cannot conclude whether the reaction will take place or not. Since the surface of any nanosheet is not uniform in terms of charge density and there are activated sites for different gas molecules based on their electrophilic and eletrophobic nature, therefore adsorption energy of a Molecule could be negative on a specific site but could be positive for another site. Thus different adsorption sites for different gas molecules should be checked, while we have also seen the orientation of the molecule determine the Hydrogen bonding between the adsorbate-adsorbent pair hence governing the Eads. Thus, I would suggest that for gas adsorption, you should not rely only on the Eads but should also take other parameters into account.
More
VOTE
Hello,
For endothermic adsorption, it is a case of activated adsorption.
I would like to suggest to search transition state.
Activated / Barrierless Adsorption question is described in our article
by Stanislav K. Ignatov, Andrey I. Okhapkin, Oleg B. Gadzhiev, Alexey G. Razuvaev, Sebastian Kunz, and Marcus Bäumer, Adsorption and Diffusion of Hydrogen on the Surface of the Pt24 Subnanoparticle. A DFT Study, J. Phys. Chem. C, 2016, 120 (33), pp 18570–18587 http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04555
I hope, it is helpful.
If it is helpful and/or instructive, I would like to ask you to cite it in an appropriate context.
Sincerely,
Oleg
http://orcid.org/0000-0003-3751-4403
http://www.researcherid.com/rid/B-4269-2014
Hello,
For endothermic adsorption, it is a case of activated adsorption.
I would like to suggest to search transition state.
Activated / Barrierless Adsorption question is described in our article
by Stanislav K. Ignatov, Andrey I. Okhapkin, Oleg B. Gadzhiev, Alexey G. Razuvaev, Sebastian Kunz, and Marcus Bäumer, Adsorption and Diffusion of Hydrogen on the Surface of the Pt24 Subnanoparticle. A DFT Study, J. Phys. Chem. C, 2016, 120 (33), pp 18570–18587 http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04555
I hope, it is helpful.
If it is helpful and/or instructive, I would like to ask you to cite it in an appropriate context.
Sincerely,
Oleg
http://orcid.org/0000-0003-3751-4403
http://www.researcherid.com/rid/B-4269-2014
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Thanks a lot @Seyedeh Tahereh Hosseini
Thanks a lot @Seyedeh Tahereh Hosseini
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Thanks to all
Thanks to all
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As suggested by Mutee Ur Rehman , Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption).
As suggested by Mutee Ur Rehman , Negative adsorption energy means the process is 'exothermic' and if the calculated Eads is negative, this means adsorption takes place (either physisorption or chemisorption).
More
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