【作者】 杨小蓉； 马家海； 王桐信； 张德清； 唐亚林； 李立璞； 侯可悦；

【Author】 YANG,Xiaorong MA Jiahai WANG,Tongxin ZHANG,Deqing TANG,Yalin~* LI,Lipun HOU,Keyue Molecular Science Centre,Institute of Chemistry,CAS P.O.Box 2709 Beijing 100080

【机构】 中国科学院化学研究所分子科学中心；

【摘要】 <正>受烷基巯基（X（CH₂）_nS-）保护的纳米金粒因其独特的物理、化学特性近来倍受关注。这种体系容易形成单分子层紧密包裹的有序结构,是一种在空气中稳定,易溶于极性和非极性有机溶剂的纳米材料。更多还原

【Abstract】 The motion of alkanethiol ligand molecules self-assembling on nano-scale gold particles was studied by the measurement of the spin-lattice relaxation time （T₁） and spin-spin relaxation time （T₂） in chloroform-d.Two kinds of ligands,Py-（CH₂）₁₂-SH and CH₃-（CH₂）₇-SH and their mixtures with different ratio are involved in this subject.NMR relaxation times of four protons at different position versus steric effect and mixing proportion in ligand mixtures were monitored.Due to different factor,each of these protons takes on special motion characteristics.For the ligands connected with Au particle,NMR T₁ and T₂ at position 2 and 3 decrease and those at position 1 and 4 increase.For mixed ligands,with the increasing of Py-（CH₂）₁₂-SH content,T₁ and T₂ at position 1,2,3 and T₁ at position 4 decrease,while NMR T₂ at position 4 increases.However,protons at different positions have different T₁ and T₂ variation speeds.The proton at position 2,due to its special location,has the largest flexibility at PY:C8/1:1.The experimental results also show that T₁ is always greater than the corresponding T₂,which indicates that ligands is in low frequency motion region in the system investigated.更多还原