Six-dimensional quantum dynamics calculations for the state-to-state scattering of H_(2)/D_(2) on the rigid Cu(100)surface have been carried out using a time-dependent wave packet approach,based on an accurate neural ...Six-dimensional quantum dynamics calculations for the state-to-state scattering of H_(2)/D_(2) on the rigid Cu(100)surface have been carried out using a time-dependent wave packet approach,based on an accurate neural network potential energy surface fit for thousands of density functional theory data computed with the opt PBE-vd W density functional.The present results are compared with previous theoretical and experimental ones regarding to the rovibrationally(in)elastic scattering of H_(2) and D_(2) from Cu(100).In particular,we test the validity of the site-averaging approximation in this system by which the six-dimensional(in)elastic scattering probabilities are compared with the weighted average of four-dimensional results over fifteen fixed sites.Specifically,the site-averaging model reproduces vibrationally elastic scattering probabilities quite well,though less well for vibrationally inelastic results at high energies.These results support the use of the site-averaging model to reduce computational costs in future investigations on the state-to-state scattering dynamics of heavy diatomic or polyatomic molecules from metal surfaces,where full-dimensional calculations are too expensive.展开更多
A crossed molecular beams, state-to-state scattering study was carried out on the F＋H2→HF＋H reaction at the collision energy of 5.02 kJ/mol, using the highly sensitive H atom Rydberg tagging time-of-flight method. ...A crossed molecular beams, state-to-state scattering study was carried out on the F＋H2→HF＋H reaction at the collision energy of 5.02 kJ/mol, using the highly sensitive H atom Rydberg tagging time-of-flight method. All the peaks in the TOF spectra can be clearly assigned to the ro-vibrational structures of the HF product. The forward scattering of the HF product at v′=3 has been observed. The small forward scattering of the HF product at v′=2 has also been detected. Detailed theoretical analysis is required in order to fully understand the dynamical origin of these forward scattering products at this high collision energy.展开更多
Reaction resonance is a frontier topic in chemical dynamics research,and it is also essential to the understanding of mechanisms of elementary chemical reactions.This short article describes an im- portant development...Reaction resonance is a frontier topic in chemical dynamics research,and it is also essential to the understanding of mechanisms of elementary chemical reactions.This short article describes an im- portant development in the frontier of research.Experimental evidence of reaction resonance has been detected in a full quantum state resolved reactive scattering study of the F+H2 reaction.Highly accurate full quantum scattering theoretical modeling shows that the reaction resonance is caused by two Feshbach resonance states.Further studies show that quantum interference is present between the two resonance states for the forward scattering product.This study is a significant step forward in our understanding of chemical reaction resonance in the benchmark F+H2 system.Further experimental studies on the effect of H2 rotational excitation on dynamical resonance have been carried out.Dy- namical resonance in the F+H2(j=1)reaction has also been observed.展开更多
The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state...The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state distributions are calculated and discussed. It is found that the rotational distribution, rather than the vibrational distribution, of the product has an obvious inversion. Due to the fact that it is a small-impact-parameter collision, its product D_2 is mainly dominated by rebound mechanism, which can lead to backward scattering at low collision energy. As the collision energy increases, the forward scattering and sideward scattering begin to appear. In addition, the backward collision is also found to happen at high collision energy, through which we can know that both the rebound mechanism and stripping mechanism exist at high collision energy.展开更多
Quantum state-to-state dynamics of the N(4S) + H-2(X1+Σ) → NH(X3Σ) + H(2S) reaction is reported in an accurate novel potential energy surface constructed by Zhai et al.(2011 J. Chem. Phys. 135 104314). The time-dep...Quantum state-to-state dynamics of the N(4S) + H-2(X1+Σ) → NH(X3Σ) + H(2S) reaction is reported in an accurate novel potential energy surface constructed by Zhai et al.(2011 J. Chem. Phys. 135 104314). The time-dependent wave packet method, which is implemented on graphics processing units, is used to calculate the differential cross sections. The influences of the collision energy on the product state-resolved integral cross sections and total differential cross sections are calculated and discussed. It is found that the products NH are predominated by the backward scattering due to the small impact parameter collisions, with only minor components being forward and sideways scattered, and have an inverted rotational distribution and no inversion in vibrational distributions; both rebound and stripping mechanisms exist in the case of high collision energies.展开更多
We present a state-to-state dynamical calculation on the reaction S++ H2→ SH+ +H based on an accurate X2 A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product...We present a state-to-state dynamical calculation on the reaction S++ H2→ SH+ +H based on an accurate X2 A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product distribution, etc.,are found to be those with characteristics of an indirect reaction. The oscillating structures appearing in reaction probability versus collision energy are considered to be the consequence of the deep potential well in the reaction. The comparison of the present total integral cross sections with the previous quasi-classical trajectory results shows that the quantum effect is more important at low collision energies. In addition, the quantum number inversion in the rotational distribution of the product is regarded as the result of the heavy–light–light mass combination, which is not effective for the vibrational excitation. For the collision energies considered, the product differential cross sections of the title reaction are mainly concentrated in the forward and backward regions, which suggests that there is a long-life intermediate complex in the reaction process.展开更多
State-to-state time-dependent quantum dynamics calculations are carried out to study F（2P） ＋ HO（2ЦП（→ O（3P） ＋ HF（1∑＋） reaction on 1^3A″ ground potential energy surface （PES）. The vibrationally resolv...State-to-state time-dependent quantum dynamics calculations are carried out to study F（2P） ＋ HO（2ЦП（→ O（3P） ＋ HF（1∑＋） reaction on 1^3A″ ground potential energy surface （PES）. The vibrationally resolved reaction probabilities and the total integral cross section agree well with the previous results. Due to the heavy-light-heavy （HLH） system and the large exoergicity, the obvious vibrational inversion is found in a state-resolved integral cross section. The total differential cross section is found to be forward-backward scattering biased with strong oscillations at energy lower than a threshold of 0.10 eV, which is the indication of the indirect complex-forming mechanism. When the collision energy increases to greater than 0.10 eV, the angular distribution of the product becomes a strong forward scattering, and almost all the products are distributed at θt = 0°. This forward-peaked distribution can be attributed to the larger J partial waves and the property of the F atom itself, which make this reaction a direct abstraction process. The state-resolved differential cross sections are basically forward-backward symmetric for v′ = 0, 1, and 2 at a collision energy of 0.07 eV; for a collision energy of 0.30 eV, it changes from backward/sideward scattering to forward peaked as v′ increasing from 0 to 3. These results indicate that the contribution of differential cross sections with more highly vibrational excited states to the total differential cross sections is principal, which further verifies the vibrational inversion in the products.展开更多
基金supported by the National Natural Science Foundation of China(No.22073089 and No.22033007)。
文摘Six-dimensional quantum dynamics calculations for the state-to-state scattering of H_(2)/D_(2) on the rigid Cu(100)surface have been carried out using a time-dependent wave packet approach,based on an accurate neural network potential energy surface fit for thousands of density functional theory data computed with the opt PBE-vd W density functional.The present results are compared with previous theoretical and experimental ones regarding to the rovibrationally(in)elastic scattering of H_(2) and D_(2) from Cu(100).In particular,we test the validity of the site-averaging approximation in this system by which the six-dimensional(in)elastic scattering probabilities are compared with the weighted average of four-dimensional results over fifteen fixed sites.Specifically,the site-averaging model reproduces vibrationally elastic scattering probabilities quite well,though less well for vibrationally inelastic results at high energies.These results support the use of the site-averaging model to reduce computational costs in future investigations on the state-to-state scattering dynamics of heavy diatomic or polyatomic molecules from metal surfaces,where full-dimensional calculations are too expensive.
基金This work was supported by the Chinese Academy of Sciences, the Ministry of Science and Technology and the National Natural Science Foundation of China.ACKN0WLEDGMENT This work was supported by the Chinese Academy of Sciences, the Ministry of Science and Technology and the National Natural Science Foundation of China.
文摘A crossed molecular beams, state-to-state scattering study was carried out on the F＋H2→HF＋H reaction at the collision energy of 5.02 kJ/mol, using the highly sensitive H atom Rydberg tagging time-of-flight method. All the peaks in the TOF spectra can be clearly assigned to the ro-vibrational structures of the HF product. The forward scattering of the HF product at v′=3 has been observed. The small forward scattering of the HF product at v′=2 has also been detected. Detailed theoretical analysis is required in order to fully understand the dynamical origin of these forward scattering products at this high collision energy.
基金Supported by the Chinese Academy of Sciences,the National Natural Science Foun-dation of China(Grant Nos.20328304,10574068,20533060 and 20525313)the Ministry of Science and Technology
文摘Reaction resonance is a frontier topic in chemical dynamics research,and it is also essential to the understanding of mechanisms of elementary chemical reactions.This short article describes an im- portant development in the frontier of research.Experimental evidence of reaction resonance has been detected in a full quantum state resolved reactive scattering study of the F+H2 reaction.Highly accurate full quantum scattering theoretical modeling shows that the reaction resonance is caused by two Feshbach resonance states.Further studies show that quantum interference is present between the two resonance states for the forward scattering product.This study is a significant step forward in our understanding of chemical reaction resonance in the benchmark F+H2 system.Further experimental studies on the effect of H2 rotational excitation on dynamical resonance have been carried out.Dy- namical resonance in the F+H2(j=1)reaction has also been observed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674198 and 11504206)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2016AP14)the Taishan Scholar Project of Shandong Province,China
文摘The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state distributions are calculated and discussed. It is found that the rotational distribution, rather than the vibrational distribution, of the product has an obvious inversion. Due to the fact that it is a small-impact-parameter collision, its product D_2 is mainly dominated by rebound mechanism, which can lead to backward scattering at low collision energy. As the collision energy increases, the forward scattering and sideward scattering begin to appear. In addition, the backward collision is also found to happen at high collision energy, through which we can know that both the rebound mechanism and stripping mechanism exist at high collision energy.
基金supported by the National Natural Science Foundation of China(Grant No.11074151)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2014AM022)
文摘Quantum state-to-state dynamics of the N(4S) + H-2(X1+Σ) → NH(X3Σ) + H(2S) reaction is reported in an accurate novel potential energy surface constructed by Zhai et al.(2011 J. Chem. Phys. 135 104314). The time-dependent wave packet method, which is implemented on graphics processing units, is used to calculate the differential cross sections. The influences of the collision energy on the product state-resolved integral cross sections and total differential cross sections are calculated and discussed. It is found that the products NH are predominated by the backward scattering due to the small impact parameter collisions, with only minor components being forward and sideways scattered, and have an inverted rotational distribution and no inversion in vibrational distributions; both rebound and stripping mechanisms exist in the case of high collision energies.
基金National Natural Science Foundation of China(Grant No.11674198)the Taishan Scholar Project of Shandong Province,China(Grant No.ts201511025)the Science Fund from the Shandong Provincial Laboratory of Biophysics.
文摘We present a state-to-state dynamical calculation on the reaction S++ H2→ SH+ +H based on an accurate X2 A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product distribution, etc.,are found to be those with characteristics of an indirect reaction. The oscillating structures appearing in reaction probability versus collision energy are considered to be the consequence of the deep potential well in the reaction. The comparison of the present total integral cross sections with the previous quasi-classical trajectory results shows that the quantum effect is more important at low collision energies. In addition, the quantum number inversion in the rotational distribution of the product is regarded as the result of the heavy–light–light mass combination, which is not effective for the vibrational excitation. For the collision energies considered, the product differential cross sections of the title reaction are mainly concentrated in the forward and backward regions, which suggests that there is a long-life intermediate complex in the reaction process.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11504206 and 11404049)the China Postdoctoral Science Foundation(CPSF)(Grant No.2014M561259)the Ph.D.Research Start-up Fund of Shandong Jiaotong University
文摘State-to-state time-dependent quantum dynamics calculations are carried out to study F（2P） ＋ HO（2ЦП（→ O（3P） ＋ HF（1∑＋） reaction on 1^3A″ ground potential energy surface （PES）. The vibrationally resolved reaction probabilities and the total integral cross section agree well with the previous results. Due to the heavy-light-heavy （HLH） system and the large exoergicity, the obvious vibrational inversion is found in a state-resolved integral cross section. The total differential cross section is found to be forward-backward scattering biased with strong oscillations at energy lower than a threshold of 0.10 eV, which is the indication of the indirect complex-forming mechanism. When the collision energy increases to greater than 0.10 eV, the angular distribution of the product becomes a strong forward scattering, and almost all the products are distributed at θt = 0°. This forward-peaked distribution can be attributed to the larger J partial waves and the property of the F atom itself, which make this reaction a direct abstraction process. The state-resolved differential cross sections are basically forward-backward symmetric for v′ = 0, 1, and 2 at a collision energy of 0.07 eV; for a collision energy of 0.30 eV, it changes from backward/sideward scattering to forward peaked as v′ increasing from 0 to 3. These results indicate that the contribution of differential cross sections with more highly vibrational excited states to the total differential cross sections is principal, which further verifies the vibrational inversion in the products.
