Faculty of Chemistry, University of Opole, 48 Oleska Street, 45-052, Opole, Poland.
Magn Reson Chem. 2013 Oct;51(10):676-81. doi: 10.1002/mrc.3999. Epub 2013 Aug 23.
The potential of nuclear magnetic resonance (NMR) technique in probing the structure of porous systems including carbon nanostructures filled with inert gases is analysed theoretically using accurate calculations of neon ((21) Ne) nuclear magnetic shieldings. The CBS estimates of (21) Ne NMR parameters were performed for single atom, its dimer and neon interacting with acetylene, ethylene and 1,3-cyclopentadiene. Several levels of theory including restricted Hartree-Fock (RHF), Møller-Plesset perturbation theory to the second order (MP2), density functional theory (DFT) with van Voorhis and Scuseria's t-dependent gradient-corrected correlation functional (VSXC), coupled cluster with single and doubles excitations (CCSD), with single, doubles and triples included in a perturbative way (CCSD(T)) and single, doubles and tripes excitations (CCSDT) combined with polarization-consistent aug-pcS-n series of basis sets were employed. The impact of neon confinement inside selected fullerene cages used as an NMR probe was studied at the RHF/pcS-2 level of theory. A sensitivity of neon probe to the proximity of multiple CC bonds in C2 H2 , C2 H4 , C5 H6 and inside C28 , C30 , C32 , C34 and C60 fullerenes was predicted from (21) Ne NMR parameters' changes. Copyright © 2013 John Wiley & Sons, Ltd.
采用精确计算氖核(^{21}Ne)核磁共振屏蔽的方法,从理论上分析了核磁共振(NMR)技术在探测包括充入惰性气体的碳纳米结构在内的多孔体系结构方面的潜力。对于单原子、二聚体以及与乙炔、乙烯和 1,3-环戊二烯相互作用的氖,我们进行了 CBS 估计的^{21}Ne 核磁共振参数的计算。所采用的理论包括限制哈特利-福克(RHF)、二阶莫利-普雷斯科特微扰理论(MP2)、带有范弗里斯和斯卡塞利亚 t 相关梯度修正关联泛函(VSXC)的密度泛函理论(DFT)、单激发和双激发耦合簇理论(CCSD)、单激发、双激发和三激发采用微扰方式包含的 CCSD(CCSD(T))以及单激发、双激发和三激发包含极化一致 aug-pcS-n 系列基组的 CCSDT 理论。在 RHF/pcS-2 理论水平上,研究了将所选富勒烯笼用作 NMR 探针时,氖在笼内受限对其的影响。根据^{21}Ne 核磁共振参数变化,预测了氖探针对 C_2H_2、C_2H_4、C_5H_6 中多个 CC 键以及 C_28、C_30、C_32、C_34 和 C_60 富勒烯内临近多个 CC 键的灵敏度。版权所有©2013 年 John Wiley & Sons, Ltd.