Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this...Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.展开更多
The structure, spectroscopic properties and chemical stability of [VS4-(CuPPh3)3 (CuCl)Br2] in CDCl3 solution have been studied by multinuclear NMR tech-nique. Two peaks with relative intensity of 1: 4 are found in th...The structure, spectroscopic properties and chemical stability of [VS4-(CuPPh3)3 (CuCl)Br2] in CDCl3 solution have been studied by multinuclear NMR tech-nique. Two peaks with relative intensity of 1: 4 are found in the31P-{1H} spectra.Some 13C-{1H} and 1H NMR peaks have the same integral intensity ratio. These com-plemented the results of 31P-{1H} NMR. The experimental results demonstrates that the PPh3 ligand bound to Cu(6) is not equivalent with the four PPh3 ligands bound toCu(2) ~Cu (5 )- It affords an evidence that the title compound in the solution keepssimilar structure to solid state.展开更多
We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve t...We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve the joint-state measurement of multi-atoms,which makes it convenient in a practical application.The scheme is also insensitive to the cavity decay and the thermal field.展开更多
Superparamagnetic iron oxide （SPIO） nanoparticle clusters are one unique form which can enhance magnetic relaxivity and improve the magnetic resonance imaging contrast at the same iron concentration, comparing to si...Superparamagnetic iron oxide （SPIO） nanoparticle clusters are one unique form which can enhance magnetic relaxivity and improve the magnetic resonance imaging contrast at the same iron concentration, comparing to single SPIO nanoparticles. Controlling of cluster size and other structural parameters have drawn great interests in this field to further improve their magnetic properties. In this study, we investigated how the interparticle distance （also known as neighbor distance） of SP10 nanocrystals within clusters affect their magnetic relaxation behaviors. To adjust the neighbor distance, different amount of cholesterol （CHO） was chosen as model spacers embedded into SPIO nanocluster systems with the help of amphiphilic diblock copolymer poly（ethylene glyco）-polyester. Small- angle X-ray scattering was applied to quantify the neighbor distance of SPIO clusters. The results demonstrated that the averaged SPIO nanocrystal neighbor distance of nan- oclusters increased with higher amount of added CHO. Moreover, these SPIO nanocrystal clusters had the promi- nent magnetic relaxation properties. Simultaneously, con- trolling of SPIO nanocrystal neighbor distance can regulate the saturation magnetization （Ms） and magnetic resonance （MR） T2 relaxation of the aggregation, and ultimately obtain better MR contrast effects with decreased neighbor distance.展开更多
Weak intermolecular interactions in aniline-pyrrole dimer clusters have been studied by the dispersion-corrected density functional theory(DFT) calculations. Two distinct types of hydrogen bonds are demonstrated with ...Weak intermolecular interactions in aniline-pyrrole dimer clusters have been studied by the dispersion-corrected density functional theory(DFT) calculations. Two distinct types of hydrogen bonds are demonstrated with optimized geometric structures and largest interaction energy moduli. Comprehensive spectroscopic analysis is also addressed revealing the orientation-dependent interactions by noting the altered red-shifts of the infrared and Raman activities. Then we employ natural bond orbital(NBO)analysis and atom in molecules(AIM) theory to have determined the origin and relative energetic contributions of the weak interactions in these systems. NBO and AIM calculations confirm the V-shaped dimer cluster is dominated by N.H···N and C.H···π hydrogen bonds, while the J-aggregated isomer is stabilized by N.H···π, n→π* and weak π···π* stacking interactions.The noncovalent interactions are also demonstrated via energy decomposition analysis associated with electrostatic and dispersion contributions.展开更多
基金supported by the National Natural Science Foundation of China(No.21773297,No.21973108,and No.21921004)supported by the National Natural Science Foundation of China(No.21805258)supported by the National Natural Science Foundation of China(No.21973107)。
文摘Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.
文摘The structure, spectroscopic properties and chemical stability of [VS4-(CuPPh3)3 (CuCl)Br2] in CDCl3 solution have been studied by multinuclear NMR tech-nique. Two peaks with relative intensity of 1: 4 are found in the31P-{1H} spectra.Some 13C-{1H} and 1H NMR peaks have the same integral intensity ratio. These com-plemented the results of 31P-{1H} NMR. The experimental results demonstrates that the PPh3 ligand bound to Cu(6) is not equivalent with the four PPh3 ligands bound toCu(2) ~Cu (5 )- It affords an evidence that the title compound in the solution keepssimilar structure to solid state.
基金supported by the National Natural Science Foundation of China(Grant Nos.61170270 and 61003290)the Specialized Research Fund for the Doctoral Program of Higher Education(Grant Nos. 20091103120014 and 20090005110010)+1 种基金the Beijing Natural Science Foundation(Grant Nos.4122008 and 1102004)the ISN Open Foundation
文摘We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve the joint-state measurement of multi-atoms,which makes it convenient in a practical application.The scheme is also insensitive to the cavity decay and the thermal field.
基金supported by the National Key Basic Research Program of China (2013CB933903)the National High Technology R&D Program of China (2012BAI23B08)the National Natural Science Foundation of China (20974065, 51173117 and 50830107)
文摘Superparamagnetic iron oxide （SPIO） nanoparticle clusters are one unique form which can enhance magnetic relaxivity and improve the magnetic resonance imaging contrast at the same iron concentration, comparing to single SPIO nanoparticles. Controlling of cluster size and other structural parameters have drawn great interests in this field to further improve their magnetic properties. In this study, we investigated how the interparticle distance （also known as neighbor distance） of SP10 nanocrystals within clusters affect their magnetic relaxation behaviors. To adjust the neighbor distance, different amount of cholesterol （CHO） was chosen as model spacers embedded into SPIO nanocluster systems with the help of amphiphilic diblock copolymer poly（ethylene glyco）-polyester. Small- angle X-ray scattering was applied to quantify the neighbor distance of SPIO clusters. The results demonstrated that the averaged SPIO nanocrystal neighbor distance of nan- oclusters increased with higher amount of added CHO. Moreover, these SPIO nanocrystal clusters had the promi- nent magnetic relaxation properties. Simultaneously, con- trolling of SPIO nanocrystal neighbor distance can regulate the saturation magnetization （Ms） and magnetic resonance （MR） T2 relaxation of the aggregation, and ultimately obtain better MR contrast effects with decreased neighbor distance.
基金supported by the National Project“Development of Advanced Scientific Instruments Based on Deep Ultraviolet Laser Source”(Y31M0112C1)the National Basic Research Program of China(2011CB808402)Z.Luo acknowledges the Young Professionals Programme in Institute of Chemistry,Chinese Academy of Sciences(ICCAS-Y3297B1261)
文摘Weak intermolecular interactions in aniline-pyrrole dimer clusters have been studied by the dispersion-corrected density functional theory(DFT) calculations. Two distinct types of hydrogen bonds are demonstrated with optimized geometric structures and largest interaction energy moduli. Comprehensive spectroscopic analysis is also addressed revealing the orientation-dependent interactions by noting the altered red-shifts of the infrared and Raman activities. Then we employ natural bond orbital(NBO)analysis and atom in molecules(AIM) theory to have determined the origin and relative energetic contributions of the weak interactions in these systems. NBO and AIM calculations confirm the V-shaped dimer cluster is dominated by N.H···N and C.H···π hydrogen bonds, while the J-aggregated isomer is stabilized by N.H···π, n→π* and weak π···π* stacking interactions.The noncovalent interactions are also demonstrated via energy decomposition analysis associated with electrostatic and dispersion contributions.
