EPR Study of H and D Atoms in Quench-Condensed Solid D$$_{2}$$2
EPR Study of H and D Atoms in Quench-Condensed Solid D$$_{2}$$2
复制标题
淬火凝聚固体 D$$_{2}$$2 中 H 和 D 原子的 EPR 研究
DOI：
--
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Y. Dmitriev
中科院分区：
文献类型：
--
作者：
Y. Dmitriev
本文介绍了H和D原子被囚禁在固体D ${2}$2矩阵中的实验研究。在1.3 - 4.2K温度下，通过在基底上骤冷冷凝气态$$_{2}$2与少量（0.15%）的分子$$_{2}$2的混合物来制备样品. EPR观测揭示了两种类型的H和D原子：窄谱线和宽谱线。为了阐明起源的中心，我们进行了分析，其中包括比较矩阵位移的超精细结构常数，考虑的饱和和自旋弛豫时间，估计的超超精细加宽，和评价的效果，隧道同位素交换反应的H和D原子的相对EPR强度。结果表明，宽谱线的H和D谱是由D $$_{2}$$2晶格中的原子取代位置引起的，而窄谱线的H和D谱是由一维结构缺陷（如位错）处的原子俘获引起的。这些被捕获的原子能够以大约4的扩散系数沿着缺陷快速移动 10 × 10 - 6 cm × 10 - 6 cm × 10 - 6 cm × 10 - 6 cm/s。结果进行了比较，早期的观察，使我们能够建立一个建议的性质，以前发现的原子中心D $${2}$2没有解释的文献。
We present an experimental study of H and D atoms trapped in a solid D$$_{2}$$2 matrix. The samples were prepared by quench condensing gaseous $$n$$nD$$_{2}$$2 with small (0.15 %) admixture of molecular $$n$$nH$$_{2}$$2 on a substrate at 1.3–4.2 K. An EPR observation revealed two types of H and D atoms: with narrow- and broad-line spectra. In order to elucidate the origin of the centers we performed an analysis that included comparing the matrix shifts of the hyperfine structure constants, considering the saturation and spin-relaxation times, estimation of the superhyperfine broadening, and evaluation of an effect which the tunneling isotope exchange reaction has on the H and D atoms relative EPR intensities. As a result, the broad-line H and D spectra were attributed to atoms at the substitutional positions in the regular D$$_{2}$$2 lattice, while the narrow-line spectra were due to atoms trapped at the one-dimensional structure imperfections (like dislocations). These trapped atoms are capable of moving quickly along the defects with a diffusion coefficient $$Dapprox 4 imes 10^{-6}$$D≈4×10-6 cm$$^{2}$$2/s. The results were compared to earlier observations which allowed us to build a suggestion about the nature of previously found atomic centers in D$$_{2}$$2 not explained in the literature.
在硝基氧自旋标签的整个运动范围内比较连续波渐进饱和 EPR 和时域饱和恢复 EPR。
DOI：
10.1016/j.jmr.2004.04.010
发表时间：
2004
期刊：
Journal of magnetic resonance (San Diego, Calif. : 1997)
影响因子：
--
作者：
Nielsen,RobertD;Canaan,Stephane;Gladden,JamesA;Gelb,MichaelH;Mailer,Colin;Robinson,BruceH
通讯作者：
Robinson,BruceH