With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn＋2. In the new cluste...With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn＋2. In the new clusters, the aluminum core-frame acts as a super-atom with n vertexes and 2n A1-A1 edges, which allow to adsorb n hydrogen atoms at the top-site and 2n at the bridge-site. Using Al12H36 as the basic unit, stable chain structures, （Al12H36）m, have been constructed following the same connection mechanism as for （A1H3）n linear polymeric structures. Apart from high hydrogen percentage per molecule, calculations have shown that these new clusters possess large heat of formation values and their combustion heat is about 4.8 times of the methane, making them a promising high energy density material.展开更多
We develop a model for the effect of thermal annealing on forming In--N dusters in GalnNP according to thermodynamics. The average energy variation for forming an In--N bond in the model is estimated according to the ...We develop a model for the effect of thermal annealing on forming In--N dusters in GalnNP according to thermodynamics. The average energy variation for forming an In--N bond in the model is estimated according to the theoretical calculation. Using the model, the added number of In--N bonds per mol of InGaNP, the added number of nearest-neighbor In atoms per N atom and the average number of nearest-neighbor In atoms per N atom after annealing are calculated. The different function of In--N clusters in InGaNP and InGaN is also discussed, which is due to the different environments around the In--N clusters.展开更多
A transfer-reaction experiment of ~9Be(~9Be,^(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ^(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the obse...A transfer-reaction experiment of ~9Be(~9Be,^(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ^(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the observed high-lying resonant states,reconstructed from theα+~6He and t+~7Li decay channels,agree with the previously reported results.In addition,two new resonances at 15.6 and 18.8 Me V are identified from the present measurement.The 18.55 Me V state is found to decay into both the t + ~7Lig:s: and t + ~7Li?(0.478 MeV) channels, with a relative branching ratio of 0:93 ± 0:33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei.展开更多
基金This work was supported by the Swedish Research Council, Swedish National Infrastructure for Computing, the National Natural Science Foundation of China （No.10534010 and No.20925311）, the Funda-mental Research Funds for the Central Universities （No.201103255）, and the China Scholarship Council.
文摘With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn＋2. In the new clusters, the aluminum core-frame acts as a super-atom with n vertexes and 2n A1-A1 edges, which allow to adsorb n hydrogen atoms at the top-site and 2n at the bridge-site. Using Al12H36 as the basic unit, stable chain structures, （Al12H36）m, have been constructed following the same connection mechanism as for （A1H3）n linear polymeric structures. Apart from high hydrogen percentage per molecule, calculations have shown that these new clusters possess large heat of formation values and their combustion heat is about 4.8 times of the methane, making them a promising high energy density material.
基金supported by the Special Funds for the Major State Basic Research Project (Grant No.2011CB301900)the National Natural Science Foundation of China (Grant Nos.60990311,60820106003,60906025,60936004 and 61177078)+1 种基金the Natural Science Foundation of Jiangsu Province (Grant Nos.BK2008019,BK2010385,BK2009255 and BK2010178)the Research Funds from NJU-Yangzhou Institute of Opto-electronics
文摘We develop a model for the effect of thermal annealing on forming In--N dusters in GalnNP according to thermodynamics. The average energy variation for forming an In--N bond in the model is estimated according to the theoretical calculation. Using the model, the added number of In--N bonds per mol of InGaNP, the added number of nearest-neighbor In atoms per N atom and the average number of nearest-neighbor In atoms per N atom after annealing are calculated. The different function of In--N clusters in InGaNP and InGaN is also discussed, which is due to the different environments around the In--N clusters.
基金supported by the National Basic Research Program of China (Grant No. 2013CB834402)the National Natural Science Foundation of China (Grant Nos. 11535004, 11275011, 11375017, and 11275001)
文摘A transfer-reaction experiment of ~9Be(~9Be,^(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ^(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the observed high-lying resonant states,reconstructed from theα+~6He and t+~7Li decay channels,agree with the previously reported results.In addition,two new resonances at 15.6 and 18.8 Me V are identified from the present measurement.The 18.55 Me V state is found to decay into both the t + ~7Lig:s: and t + ~7Li?(0.478 MeV) channels, with a relative branching ratio of 0:93 ± 0:33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei.
