Pure Nuclear Quadrupole Resonance Studies of Glass Structure

玻璃结构的纯核四极共振研究

• 批准号: 8920532
• 负责人: Philip Bray
• 金额: $ 7.5万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-05-15 至 1992-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8920532&HistoricalAwards=false
• 关键词: Pure; Nuclear; Quadrupole; Resonance; Studies

Advances in nuclear quadrupole resonance (NQR) spectroscopy have suggested the possibility one may be able to determine whether borate glasses contain the structural groupings (boroxyl, diborate, metaborate, etc.) that are found in the crystalline compounds of the borate systems. A new regenerative NQR spectrometer yields boron signals of about 100 at 1 MHz and permits measurements down to 200 kHz. The new NQR results allow the quadrupole coupling and asymmetry parameters to be determined to better than 1%, more than an order of magnitude better than from NMR spectra. NQR spectroscopy is yielding highly accurate values of these parameters in crystals and glasses, which should permit a positive identification of the structural groupings in borate binary glasses. Extensions to terniary glass systems are also planned. There are also plans to extend the work to aluminum nuclei to accurately determine the electric field gradient tensors at the aluminum site to ascertain the symmetry, coordination, and chemical bonding of the aluminum.

核四极共振（NQR）光谱学的进展 提出了一种可能性，人们可以确定是否 硼酸盐玻璃含有结构基团（硼氧基， 二硼酸盐、偏硼酸盐等）存在于水晶中 硼酸盐体系的化合物。 一种新的再生式核四极谐振器 质谱仪在1MHz下产生约100的硼信号， 允许测量低至200 kHz。 新的NQR结果允许 四极耦合和不对称参数有待确定 好于1%，好于 核磁共振谱。 核四极矩共振光谱学能够产生高度精确的 晶体和玻璃中这些参数的值， 允许积极识别的结构分组， 硼酸盐二元玻璃 三元玻璃系统的扩展是 也计划。 还计划将这项工作扩大到 铝原子核来精确地确定电场 在铝位点的梯度张量以确定对称性， 铝的配位和化学键合。