Pub Date : 2015-06-01DOI: 10.4208/jams.041615.052015a
W. Ren
{"title":"An algebraic method to determine the local field of condensed system","authors":"W. Ren","doi":"10.4208/jams.041615.052015a","DOIUrl":"https://doi.org/10.4208/jams.041615.052015a","url":null,"abstract":"","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"1 1","pages":"145-154"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82271724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.4208/jams.091215.101815a
Q. Meng
Photoassociation reaction is the process in which two colliding atoms (or the colliding atom-molecule system) absorb a photon to form an excited molecule. Since the researches based on the ultracold atomic and molecular systems have attracted great attention both from theorists and experimentalists, the ultracold photoassociation reaction is becoming an ascendant research field. In this paper, we review briefly the investigation history of the photoassociation reaction for ultracold atoms, especially the basic theory of collision and the photoassociation in different light fields, and the research on the external-field manipulation of ultracold atoms collisions is also prospected. PACS: 34.10.+x, 34.50.Rk, 39.25.+k,82.30.Nr
{"title":"The photoassociation reaction of ultracold atoms","authors":"Q. Meng","doi":"10.4208/jams.091215.101815a","DOIUrl":"https://doi.org/10.4208/jams.091215.101815a","url":null,"abstract":"Photoassociation reaction is the process in which two colliding atoms (or the colliding atom-molecule system) absorb a photon to form an excited molecule. Since the researches based on the ultracold atomic and molecular systems have attracted great attention both from theorists and experimentalists, the ultracold photoassociation reaction is becoming an ascendant research field. In this paper, we review briefly the investigation history of the photoassociation reaction for ultracold atoms, especially the basic theory of collision and the photoassociation in different light fields, and the research on the external-field manipulation of ultracold atoms collisions is also prospected. PACS: 34.10.+x, 34.50.Rk, 39.25.+k,82.30.Nr","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"70 1","pages":"234-242"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74539733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.4208/JAMS.071615.081615A
D. Yang
{"title":"ESIPT of 1-[N-(2-pyridyl) aminomethylidene]-2(1H)-Naphtalenone: A TDDFT study","authors":"D. Yang","doi":"10.4208/JAMS.071615.081615A","DOIUrl":"https://doi.org/10.4208/JAMS.071615.081615A","url":null,"abstract":"","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"47 1","pages":"215-224"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79877269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.4208/JAMS.010114.022015A
Bo Zhou, Q. Wei
. Product Polarizations for the exchange reaction H’+HS and its isotopic variants on an accurate 1A’potential energy surface have been studied at collision energies of 10 kcal/mol by using the quasi-classical trajectory method (QCT). Product rotational angular momentum distributions P ( θ r ) and P ( φ r ) are calculated in the center-of-mass (CM) frame. Moreover, three generalized polarization-dependent differential cross sections (PDDCSs) are also computed. The results demonstrated that the isotopic effect displays sensitive effect on the product vector correlations. The reaction mechanism was discussed based on the properties of stereodynamics and the reactive trajectories.
{"title":"Quasiclassical Trajectory Study of Stereodynamics for Exchange Reactions H'(D')+H(D)S","authors":"Bo Zhou, Q. Wei","doi":"10.4208/JAMS.010114.022015A","DOIUrl":"https://doi.org/10.4208/JAMS.010114.022015A","url":null,"abstract":". Product Polarizations for the exchange reaction H’+HS and its isotopic variants on an accurate 1A’potential energy surface have been studied at collision energies of 10 kcal/mol by using the quasi-classical trajectory method (QCT). Product rotational angular momentum distributions P ( θ r ) and P ( φ r ) are calculated in the center-of-mass (CM) frame. Moreover, three generalized polarization-dependent differential cross sections (PDDCSs) are also computed. The results demonstrated that the isotopic effect displays sensitive effect on the product vector correlations. The reaction mechanism was discussed based on the properties of stereodynamics and the reactive trajectories.","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"19 1","pages":"52-62"},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88606065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.4208/JAMS.120214.013115A
Junsheng Chen, Li Zhao, Yang Yang, Tianshu Chu
Our density functional theory (DFT)/time-dependent DFT (TDDFT) calculations for the sensing mechanism of a series of sulfoxide based metal-responsive fluorescent chemosensors, suggested that the intramolecular charge transfer (ICT) is not a reasonable mechanism for these chemosensors. The calculated electronic transition energies, the corresponding oscillator strengths of these chemosensors and the involving frontier molecular orbital analysis indicated that there is no obviously ICT state with a transition oscillator strength approaching to zero. The fluorescence quenching of these chemosensors cannot be explained by ICT process. The ground state optimized structures of chemosensors and their complexes indicated that there might be twisted excited configuration for these chemosensors and the twisted excited state configuration may response for the fluorescence quenching. The configuration change can be blocked in the Zn complex that is responsible for these complexes showing fluorescence emission enhancement. In order to understand the function of the sulfoxides group in these metal-responsive fluorescent chemosensors, excited state configuration optimization as well as the excited state hydrogen bond effect on the fluorescence enhancement in the aqueous solvent will be conducted. PACS: 34.70.+e; 42.70.-a
{"title":"Sulfoxides as response elements for fluorescent chemosensors: Does it work?","authors":"Junsheng Chen, Li Zhao, Yang Yang, Tianshu Chu","doi":"10.4208/JAMS.120214.013115A","DOIUrl":"https://doi.org/10.4208/JAMS.120214.013115A","url":null,"abstract":"Our density functional theory (DFT)/time-dependent DFT (TDDFT) calculations for the sensing mechanism of a series of sulfoxide based metal-responsive fluorescent chemosensors, suggested that the intramolecular charge transfer (ICT) is not a reasonable mechanism for these chemosensors. The calculated electronic transition energies, the corresponding oscillator strengths of these chemosensors and the involving frontier molecular orbital analysis indicated that there is no obviously ICT state with a transition oscillator strength approaching to zero. The fluorescence quenching of these chemosensors cannot be explained by ICT process. The ground state optimized structures of chemosensors and their complexes indicated that there might be twisted excited configuration for these chemosensors and the twisted excited state configuration may response for the fluorescence quenching. The configuration change can be blocked in the Zn complex that is responsible for these complexes showing fluorescence emission enhancement. In order to understand the function of the sulfoxides group in these metal-responsive fluorescent chemosensors, excited state configuration optimization as well as the excited state hydrogen bond effect on the fluorescence enhancement in the aqueous solvent will be conducted. PACS: 34.70.+e; 42.70.-a","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"34 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89853922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.4208/jams.123014.021515a
Yunhui Wang, K. Deng, R. Lu
{"title":"Quantum dynamics study of H exchange reaction of H'(2S) + CH(X2Π) → H(2S) + CH'(X2Π) and Isotope Reactions of H(2S) + CH(X2Π) → C(1D) + H2(X1Σ+g)","authors":"Yunhui Wang, K. Deng, R. Lu","doi":"10.4208/jams.123014.021515a","DOIUrl":"https://doi.org/10.4208/jams.123014.021515a","url":null,"abstract":"","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"30 1","pages":"11-22"},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74589315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.4208/JAMS.100314.010115A
Yanling Cui, Pengyu Li, Jing Wang, P. Song, Lixin Xia
Based on the time-dependent density functional theory (TDDFT), the excited state intramolecular proton transfer (ESIPT) mechanism of a new compound 1 chromophore synthesized and designed by Liu et al. [Journal of Photochemistry and Photobiology B: Biology., 138 (2014), 75-79] has been investigated theoretically. The calculations of primary bond lengths, angles and the IR vibrational spectra verified the intramolecular hydrogen bond was strengthened. The fact that reproducing the experimental absorbance and fluorescence emission spectra well theoretically demonstrates that the TDDFT theory we adopted is reasonable and effective. In addition, intramolecular charge transfer based on the frontier molecular orbitals demonstrated the indication of the ESIPT reaction. The constructed potential energy curves of ground state and the first excited state based on keeping the O-H distance fixed at a serious of values have been used to illustrate the ESIPT process. A little barrier of 2.45 kcal/mol in the first excited state potential energy curve provided the transfer mechanism. Further, the phenomenon of fluorescence quenching has been explained reasonably based on the ESIPT mechanism. PACS: 31.25.Jf; 82.39.Jn
{"title":"An investigation of excited-state intramolecular proton transfer mechanism of new chromophore","authors":"Yanling Cui, Pengyu Li, Jing Wang, P. Song, Lixin Xia","doi":"10.4208/JAMS.100314.010115A","DOIUrl":"https://doi.org/10.4208/JAMS.100314.010115A","url":null,"abstract":"Based on the time-dependent density functional theory (TDDFT), the excited state intramolecular proton transfer (ESIPT) mechanism of a new compound 1 chromophore synthesized and designed by Liu et al. [Journal of Photochemistry and Photobiology B: Biology., 138 (2014), 75-79] has been investigated theoretically. The calculations of primary bond lengths, angles and the IR vibrational spectra verified the intramolecular hydrogen bond was strengthened. The fact that reproducing the experimental absorbance and fluorescence emission spectra well theoretically demonstrates that the TDDFT theory we adopted is reasonable and effective. In addition, intramolecular charge transfer based on the frontier molecular orbitals demonstrated the indication of the ESIPT reaction. The constructed potential energy curves of ground state and the first excited state based on keeping the O-H distance fixed at a serious of values have been used to illustrate the ESIPT process. A little barrier of 2.45 kcal/mol in the first excited state potential energy curve provided the transfer mechanism. Further, the phenomenon of fluorescence quenching has been explained reasonably based on the ESIPT mechanism. PACS: 31.25.Jf; 82.39.Jn","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"43 1","pages":"23-33"},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82675740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-03-01DOI: 10.4208/JAMS.122214.022515A
Chun-yuan Hou, G. Chai, Haijun Li
A quantum mechanical approach has been used to investigate the antioxidative mechanism for scavenging •OOH and •OH radicals using mangiferin in solution phase. Mangiferin is also used as a potent applicant for organic semiconductor. The charge-transport properties in mangiferin have been studied based on the first-principle DFT combined with the Marcus-Hush theory. Density functional theory (DFT) calculations at the B3LYP/6-311+G(d,p) level were used to optimize mangiferin and its different forms. The lowest theoretical bond dissociation enthalpy (BDE) value for 7-OH site of mangiferin in water, indicates that 7-OH group is important in the antioxidant activity. The relative values of enthalpies also show that oxidation of mangiferin by •OOH and •OH radical is an exothermic process. The predicted maximum electron mobility value of mangiferin is 0.148 cm2 V−1 s−1, which appears at the orientation angle near 49◦/311◦ of conducting channel on the reference planes ab. Theoretical investigation of natural semiconductors is helpful for designing higher performance electronic materials used in biochemical and industrial field to replace expensive and rare organic materials. PACS: 34.70.+e; 42.70.Nq
{"title":"Antioxidative mechanism and anisotropic charge transport properties of mangiferin: A theoretical study","authors":"Chun-yuan Hou, G. Chai, Haijun Li","doi":"10.4208/JAMS.122214.022515A","DOIUrl":"https://doi.org/10.4208/JAMS.122214.022515A","url":null,"abstract":"A quantum mechanical approach has been used to investigate the antioxidative mechanism for scavenging •OOH and •OH radicals using mangiferin in solution phase. Mangiferin is also used as a potent applicant for organic semiconductor. The charge-transport properties in mangiferin have been studied based on the first-principle DFT combined with the Marcus-Hush theory. Density functional theory (DFT) calculations at the B3LYP/6-311+G(d,p) level were used to optimize mangiferin and its different forms. The lowest theoretical bond dissociation enthalpy (BDE) value for 7-OH site of mangiferin in water, indicates that 7-OH group is important in the antioxidant activity. The relative values of enthalpies also show that oxidation of mangiferin by •OOH and •OH radical is an exothermic process. The predicted maximum electron mobility value of mangiferin is 0.148 cm2 V−1 s−1, which appears at the orientation angle near 49◦/311◦ of conducting channel on the reference planes ab. Theoretical investigation of natural semiconductors is helpful for designing higher performance electronic materials used in biochemical and industrial field to replace expensive and rare organic materials. PACS: 34.70.+e; 42.70.Nq","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"1 1","pages":"34-51"},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83000860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this article, we do a research on the chiral shift process of the isolated alpha alanine molecule using the basis set of 6-31+g(d,p), which is based on density functional theory B3LYP. Furthermore, the chiral transition path reaction potential en- ergy surface of ibuprofen molecule is drawn by looking for the extreme value point structure including the transition state and intermediate. Finally, the geometry and electronic structure properties of extreme value point are also analyzed. The results show that there are two achieve reaction paths of ibuprofen from S-type to R-type. Path 1 consists of three transition states and two intermediate states. Path 2 includes four transition states and three intermediate states. On the reaction path, the greatest barrier which is from the transfer of hydrogen in chiral carbon to oxygen in carboxyl, is 73.54 Kcal/mol. The researchprovides a theoretical reference to further realize some important application value over the chiral transition reaction control of point chiral molecule.
{"title":"The theoretical research on the chiral transition of ibuprofen molecules under isolated conditions","authors":"Zuocheng Wang, Fengliang Liu, Li-ping Wang, Hua Tong, Tianrong Yu, Lily Dong","doi":"10.4208/JAMS.022514.031414A","DOIUrl":"https://doi.org/10.4208/JAMS.022514.031414A","url":null,"abstract":"In this article, we do a research on the chiral shift process of the isolated alpha alanine molecule using the basis set of 6-31+g(d,p), which is based on density functional theory B3LYP. Furthermore, the chiral transition path reaction potential en- ergy surface of ibuprofen molecule is drawn by looking for the extreme value point structure including the transition state and intermediate. Finally, the geometry and electronic structure properties of extreme value point are also analyzed. The results show that there are two achieve reaction paths of ibuprofen from S-type to R-type. Path 1 consists of three transition states and two intermediate states. Path 2 includes four transition states and three intermediate states. On the reaction path, the greatest barrier which is from the transfer of hydrogen in chiral carbon to oxygen in carboxyl, is 73.54 Kcal/mol. The researchprovides a theoretical reference to further realize some important application value over the chiral transition reaction control of point chiral molecule.","PeriodicalId":15131,"journal":{"name":"Journal of Atomic and Molecular Sciences","volume":"55 1","pages":"289-300"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80215110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}