摹略万物之然——后期墨家认识论

后期墨家在继承墨子唯物思想的基础上,论述了认识的基础、认识的过程及认识过程中的阶段性、认识所得知识的不同来源及种类,批判了以往认识论中的一些错误命题。后期墨家的认识论系统,感性、理性认识并重,理性认识以感性认识为基础。这种认识论对认识主体作用的强调有重要的理论与现实意义。

Kinetics and Dynamics of the H(^(2)S)+NO(X^(2)Π)→N(^(4)S)+OH(X^(2)Π) Reaction:A Quasi-classical Trajectory Study

A quasi-classical trajectory study of the H(^(2)S)+NO(X^(2)Π)→N(^(4)S)+OH(X^(2)Π) reaction kinetics and dynamics is reported on an accurate potential energy surface.The total integral cross sections of the reaction were calculated at the collision energy ranging from 2.00 e V to 2.80 e V.It was found that the total reaction integral cross section increases monotonically with the collision energy.Specifically at the collision energy range of 2.40-2.57 e V,our calculated results are in reasonably good agreement with the experimental data.The calculated thermal rate constants are in fairly good agreement with available experimental results.Through the trajectory analysis at the collision energy of 2.57 e V,it was found that the title reaction is dominated by the indirect trajectories(1.4 times more compared to the direct trajectories),which sheds light on the reaction dynamics of the title reaction in the high collision energy range.

Three-Dimensional Diabatic Potential Energy Surfaces of Thiophenol withNeural Networks

Three-dimensional(3D)diabatic potential energy surfaces(PESs)of thiophenol involving the S0,and coupled 1ππ^(*) and 1πσ^(*) states were constructed by a neural network approach.Specifically,the diabatization of the PESs for the 1ππ^(*) and 1πσ^(*) states was achieved by the fitting approach with neural networks,which was merely based on adiabatic energies but with the correct symmetry constraint on the off-diagonal term in the diabatic potential energy matrix.The root mean square errors(RMSEs)of the neural network fitting for all three states were found to be quite small(<4 meV),which suggests the high accuracy of the neural network method.The computed low-lying energy levels of the S_(0) state and lifetime of the 0^(0) state of S_(1) on the neural network PESs are found to be in good agreement with those from the earlier diabatic PESs,which validates the accuracy and reliability of the PESs fitted by the neural network approach.

EOM-CCSD-Based Neural Network Diabatic Potential Energy Matrix for ^(1)πσ^(*)-Mediated Photodissociation of Thiophenol

A new diabatic potential energy matrix(PEM)of the coupled~^(1)ππ^(*)and~1πσ*states for the~1πσ*-mediated photodissociation of thiophenol was constructed using a neural network(NN)approach.The diabatization of the PEM was specifically achieved by our recent method[Chin.J.Chem.Phys.34,825(2021)],which was based on adiabatic energies without the associated costly derivative couplings.The equation of motion coupled cluster with single and double excitations(EOM-CCSD)method was employed to compute adiabatic energies of two excited states in this work due to its high accuracy,simplicity,and efficiency.The PEM includes three dimensionalities,namely the S-H stretch,C-S-H bend,and C-C-S-H torsional coordinates.The root mean square errors of the NN fitting for the S1 and S2 states are 0.89 and 1.33 me V,respectively,suggesting the high accuracy of the NN method as expected.The calculated lifetimes of the S1 vibronic 00 and31 states are found to be in reasonably good agreement with available theoretical and experimental results,which validates the new EOM-CCSD-based PEM fitted by the NN approach.The combination of the diabatization scheme solely based on the adiabatic energies and the use of EOM-CCSD method makes the construction of reliable diabatic PEM quite simple and efficient.

Threshold Structures in Hadron Spectrum and Hadronic Molecules

Numerous candidates for exotic hadrons have been detected experimentally in the past two decades,predominantly near the threshold of a pair of hadrons.This study aims to investigate the overall behavior of nearthreshold line shapes in invariant mass distributions.It is noteworthy that the threshold cusp might manifest as a peak only in channels with attractive interaction.The assertion is made that there should be near-threshold structures for any heavy-quark and heavy-antiquark hadron pairs exhibiting attractive interaction at the threshold,as observed in the invariant mass distribution of heavy quarkonium and light hadrons that couple to the open-flavor hadron pair.Furthermore,we have conducted an analysis of potential hadronic molecules comprising pairs of heavy hadrons,utilizing the Bethe-Salpeter equation with constant interactions derived from the one-boson-exchange model.Observed candidates for these hadronic molecules are in good agreement with our predicted spectrum.

Shape Decoupling Effects and Rotation of Deformed Halo Nuclei

With the development of radioactive-ion-beam facilities,many exotic phenomena have been discovered or predicted in the nuclei far from the stability line,including cluster structure,shell structure,deformed halo,and shape decoupling effects.The study of exotic nuclear phenomena is at the frontier of nuclear physics nowadays.The covariant density functional theory(CDFT)is one of the most successful microscopic models in describing the structure of nuclei in almost the whole nuclear chart.Within the framework of CDFT,toward a proper treatment of deformation and weak binding,the deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc)has been developed.In this contribution,we review the applications and extensions of the DRHBc theory to the study of exotic nuclei.The DRHBc theory has been used to investigate the deformed halos in B,C,Ne,Na,and Mg isotopes and the theoretical descriptions are reasonably consistent with available data.A DRHBc Mass Table Collaboration has been founded,aiming at a high precision nuclear mass table with deformation and continuum effects included,which is underway.By implementing the angular momentum projection based on the DRHBc theory,the rotational excitations of deformed halos have been investigated and it is shown that the deformed halos and shape decoupling effects also exist in the low-lying rotational excitation states of deformed halo nuclei.

Microscopic Cluster Study of the ^(10)Be Nucleus

Using a microscopic four-body cluster model,we investigate the spectral properties and structural configurations of the ^(10)Be nucleus.We calculate physical quantities such as the root-mean-squared(r.m.s.)radii and electromagnetic transition strengths.The theoretical results for the energies and certain electromagnetic transition strengths of the low-lying states show good agreement with experimental data.In particular,the enhancement of the r.m.s.radius and isoscalar monopole transition strength of the O_(3)^(+) state indicates a well-developed cluster structure.We obtained three 1-states in E_(x)<15 MeV that show remarkable dipole transition strengths,suggesting that the 1-states may have cluster structure.Using the obtained wave functions,we calculate the reduced-width amplitudes(RWAs)to investigate the SHe+α and'Be+n two-body cluster structures in ^(10)Be.The results suggest that the lowlying states show the two-body ^(6)He+α and ^(9)Be+n configuration,with the ^(6)He+α components of the two-body structure diminishing as the energy increases,which due to the breakup of He and ^(9)Be at higher excitation energies.Moreover,a few states above the α+α+n+n threshold still exhibit significant 9Be+n components.

Exploring the Feasibility of Producing Superheavy Nuclei in the Proton Evaporation Channel

The feasibility of producing superheavy nuclei in proton evaporation channels was systematically studied within the dinuclear system(DNS)model.Due to the Z=114 proton-shell,one can synthesize Fl isotopes in proton evaporation channels.We only considered the case of evaporating one proton first and then n neutrons in this work,other cases were ignored due to the small cross-section.The production cross sections of unknown isotopes ^(290,291)Fl in ^(38)S+^(255)Es reaction are the highest compared with ^(50)Ti+^(243)Np and ^(54)Cr+^(239)Pa reactions,and the maximum cross sections are 1.1 and 15.1 pb,respectively.^(42)S+^(254)Es is a promising candidate to approach the island of stability as the radioactive beam facilities are upgraded in the future,and the production cross sections of ^(291−294)Fl in that reaction are estimated to be 3.2,6.0,4.0,and 0.1 pb,respectively.