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1.
J Chem Theory Comput ; 20(9): 3449-3461, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691764

RESUMO

Recently, a combined study of high-resolution molecular crossed beam experiment and accurate full-dimensional time-dependent theory, including full spin-orbit characteristics on the effect of electronic spin and orbital angular momenta in the F + HD reaction, was reported by some of us, focusing on the partial wave resonance phenomenon (Science 2021, 371, 936-940). It revealed that the time-dependent theory could explain all of the details observed in the high-resolution experiment. Here, we develop two time-independent close-coupling methods using hyperspherical coordinates, including the two-state model, where only a part of the spin-orbit characteristics is considered, and the six-state model, where the full spin-orbit characteristics is considered. With these two newly developed theoretical models and the adiabatic theoretical model, the detailed reaction dynamics of the F + HD (v = 0, j = 0) reaction and the Cl + H2 (v = 0, j = 0) reaction are investigated and compared. Some of the results are compared with the time-dependent quantum wave packet theory and the experimental observations, and good agreements have been obtained, which suggests the validity of the pure-procession approximation in the six-state model using different theoretical methods. This work demonstrates the ability of the reactive scattering theory including full spin-orbit characteristics for describing the reactions of a halogen atom plus hydrogen molecule and its isotopologues.

2.
J Phys Chem A ; 128(17): 3301-3310, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38648526

RESUMO

The impact of non-Born-Oppenheimer couplings on the isotopic effects in the reaction of the Cl(2P) atom with the HD (v = 0, j = 0) molecule is investigated with our recently developed nonadiabatic time-independent quantum scattering methods, where the full open-shell characteristics are included in the six-state model, and also with the recently developed two-state model solving by time-independent methods, where part of the open-shell characteristic is included. The same reaction is also calculated with the simple adiabatic model using the lowest adiabatic potential energy surface. Compared with the results from different models, it is found that the reactivity of the Cl + HD → HCl + D channel is significantly overestimated in the adiabatic model. In contrast, the reactivity of the other channel agrees well with the nonadiabatic models. This is due to the van der Waals well in the reactant channel being changed a lot by including the nonadiabatic couplings. These quantum dynamics calculations suggest that sometimes the adiabatic model should be used with caution; otherwise, it may result in significant deviations for some reactions.

3.
J Phys Chem A ; 128(18): 3726-3741, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38666315

RESUMO

Although the reactant-product decoupling (RPD) technique was proposed over two decades ago, it remains an efficient approach for calculating product state-resolved information on some simple direct reactions using the quantum wave packet method. In the past, usually the RPD technique employed the collocation method to transform the wave function between reactant and product arrangements, which requires quite large computational efforts. In this work, the intermediate coordinate (IC) method is employed to realize the RPD technique. Numerical examples demonstrate that this new IC RPD (IRPD) technique has superior computational efficiency compared with the original method employing the collocation method. Especially, the new IRPD technique significantly saves disk space and computer memory. To illustrate the features of our new method, the total reaction probabilities of the H + H2, H + Br2, and F + H2 reactions with J = 0 and the differential cross sections of the H + H2 and F + H2 reactions at a series of collision energy are calculated and presented. With this efficient and effective new RPD technique, the Li + HF reaction, which involves sharp resonances with long-range wave functions in the van der Waals wells in both the reactant and product arrangements, is also calculated with several J at the product state-resolved level to reveal the ability of the RPD technique for describing resonance wave functions. With these numerical examples, it is found that, for the reaction with resonances, the RPD approach should be applied carefully. Otherwise, it is very possible that the resonances could disappear with the application of the RPD technique.

4.
Science ; 371(6532): 936-940, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33632844

RESUMO

The effect of electron spin-orbit interactions on chemical reaction dynamics has been a topic of much research interest. Here we report a combined experimental and theoretical study on the effect of electron spin and orbital angular momentum in the F + HD → HF + D reaction. Using a high-resolution imaging technique, we observed a peculiar horseshoe-shaped pattern in the product rotational-state-resolved differential cross sections around the forward-scattering direction. The unusual dynamics pattern could only be explained properly by highly accurate quantum dynamics theory when full spin-orbit characteristics were considered. Theoretical analysis revealed that the horseshoe pattern was largely the result of quantum interference between spin-orbit split-partial-wave resonances with positive and negative parities, providing a distinctive example of how spin-orbit interaction can effectively influence reaction dynamics.

5.
Int J Nanomedicine ; 15: 1363-1372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184591

RESUMO

PURPOSE: In this study, we constructed novel brain-targeting complexes (U2-AuNP) by conjugating aptamer U2 to the gold nanoparticle (AuNPs) surface as a promising option for GBM therapy. MATERIALS AND METHODS: The properties of the U2-AuNP complexes were thoroughly characterized. Then, we detected the in vitro effects of U2-AuNP in U87-EGFRvIII cell lines and the in vivo antitumor effects of U2-AuNP in GBM-bearing mice. Furthermore, we explored the inhibition mechanism of U2-AuNP in U87-EGFRvIII cell lines. RESULTS: We found that U2-AuNP inhibits the proliferation and invasion of U87-EGFRvIII cell lines and prolongs the survival time of GBM-bearing mice. We found that U2-AuNP can inhibit the EGFR-related pathway and prevent DNA damage repair in GBM cells. CONCLUSION: These results reveal the promising potential of U2-AuNP as a drug candidate for targeted therapy in GBM.


Assuntos
Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Ouro/química , Nanopartículas Metálicas/administração & dosagem , Animais , Antineoplásicos/química , Apoptose , Aptâmeros de Nucleotídeos/química , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Masculino , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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