Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some m...Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some modern density functional methods including B97-D, BLYP-D3, M06-2X, XYG3, and force field models including CHARMM, AMBER, MM3, AMOEBA on six important interaction modes of bz2. Our results not only highlight the usefulness of these cost-effective methods, which can be used as economic substitutes of the expensive CCSD(T) for complex real-world systems, but also indicate their weakness in the description of the π-π interactions, which points to the future direction for further improvements.展开更多
In the paper,we consider the transport of a two-dimensional random walk.The velocity and the dispersionof this two-dimensional random walk are derived.It mainly show that:(i)by controlling the values of the transition...In the paper,we consider the transport of a two-dimensional random walk.The velocity and the dispersionof this two-dimensional random walk are derived.It mainly show that:(i)by controlling the values of the transition rates,the direction of the random walk can be reversed;(ii)for some suitably selected transition rates,our two-dimensionalrandom walk can be efficient in comparison with the one-dimensional random walk.Our work is motivated in part by thechallenge to explain the unidirectional transport of motor proteins.When the motor proteins move at the turn pointsof their tracks(i.e.,the cytoskeleton filaments and the DNA molecular tubes),some of our results in this paper can beused to deal with the problem.展开更多
Sound propagation and the initial value problems in gas mixtures of two components are investigated. By using the eigen theory of linearized Boltzmann equations, a model equations is formed, with the use of the Fourie...Sound propagation and the initial value problems in gas mixtures of two components are investigated. By using the eigen theory of linearized Boltzmann equations, a model equations is formed, with the use of the Fourier-Laplace transform for model equations derived, the dispersion relations for both components are obtained.展开更多
Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free elect...Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free electron value for the liquid alkali metals and their equiatomic binary alloys for the first time. In the present computation, the use of pseudo-alloy-atom model (PAA) is proposed and found successful. The influence of the six different forms of the local field correction functions proposed by Hartree (H), Vashishta Singwi (VS), Taylor (T), lehimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) on the aforesaid electronic properties is examined explicitly, which reflects the varying effects of screening. The depth of the negative hump in the electron dispersion of liquid alkalis decreases in the order Li --→ K, except for Rb and Cs, it increases. The results of alloys are in predictive nature.展开更多
基金Acknowledgments: This work was supported by the National Natural Science Foundation of China (No.91027044) and the Ministry of Science and Technology (No.2011CB808505).
文摘Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some modern density functional methods including B97-D, BLYP-D3, M06-2X, XYG3, and force field models including CHARMM, AMBER, MM3, AMOEBA on six important interaction modes of bz2. Our results not only highlight the usefulness of these cost-effective methods, which can be used as economic substitutes of the expensive CCSD(T) for complex real-world systems, but also indicate their weakness in the description of the π-π interactions, which points to the future direction for further improvements.
基金Supported by National Natural Science Foundation of China under Grant No.10975079by K.C.Wong Magna Fund in Ningbo University in China,and the Natural Science Foundation of Ningbo in China under Grant No.2008A61003
文摘In the paper,we consider the transport of a two-dimensional random walk.The velocity and the dispersionof this two-dimensional random walk are derived.It mainly show that:(i)by controlling the values of the transition rates,the direction of the random walk can be reversed;(ii)for some suitably selected transition rates,our two-dimensionalrandom walk can be efficient in comparison with the one-dimensional random walk.Our work is motivated in part by thechallenge to explain the unidirectional transport of motor proteins.When the motor proteins move at the turn pointsof their tracks(i.e.,the cytoskeleton filaments and the DNA molecular tubes),some of our results in this paper can beused to deal with the problem.
基金Supported by National Natural Science Foundation of China under Grant No.10861008the "211 Project" Innovative Talents Training Program of Inner Mongolia University and Grant-in-Aid for Scientific Research from Inner Mongolia University of Technology under Grant No.ZS201032
文摘Sound propagation and the initial value problems in gas mixtures of two components are investigated. By using the eigen theory of linearized Boltzmann equations, a model equations is formed, with the use of the Fourier-Laplace transform for model equations derived, the dispersion relations for both components are obtained.
文摘Ashcroft's local empty core (EMC) model pseudopotential in the second-order perturbation theory is used to study the electron dispersion relation, the Fermi energy, and deviation in the Fermi energy from free electron value for the liquid alkali metals and their equiatomic binary alloys for the first time. In the present computation, the use of pseudo-alloy-atom model (PAA) is proposed and found successful. The influence of the six different forms of the local field correction functions proposed by Hartree (H), Vashishta Singwi (VS), Taylor (T), lehimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) on the aforesaid electronic properties is examined explicitly, which reflects the varying effects of screening. The depth of the negative hump in the electron dispersion of liquid alkalis decreases in the order Li --→ K, except for Rb and Cs, it increases. The results of alloys are in predictive nature.