五氧硼酸钾结构的~1H　NMR研究  

￣1H NMR STUDY ON THE STRUCTURE OF POTASSIUM PENTABORATE TETRAHYDRATE

作　　者：李子荣[1] 孟庆安[1] 陈万春[1] 谢安云[1] 

机构地区：[1]中国科学院物理研究所

出　　处：《波谱学杂志》1995年第1期79-85,共7页Chinese Journal of Magnetic Resonance

摘　　要：给出相对于外磁场不同取向的五氧硼酸钾（ＫＢ５）单晶的１ＨＮＭＲ室温谱．发现当外磁场在晶体的ｂｃ平面里，１ＨＮＭＲ谱最多有６个峰．而在ａｈ或ａｃ平面里，最多仅有５个峰．用计算机拟合ＮＭＲ谱表明：在五氧硼酸钾中，氢原子是以羟基和水分子集团的形式存在．在羟基集团中，Ｏ—Ｈ的距离为０．１００５±０．００１ｎｍ和０．１０５４±０．００１ｎｍ；而在水分子中，Ｏ—Ｈ的距离为０．０９８３±０．００１ｎｍ和０．０９６８±０．００１ｎｍ，并且Ｈ—Ｏ—Ｈ夹角为１０８°±１°．这些显示本文的数据与中子衍射结果相近，而Ｘ射线衍射所得到的质子位置的数据则与我们的结果相距甚远．H NMR spectra of single optal of potassium pentaborate tetrahydrate(KB5) have ben obtained at RT with different orientations with respect to the external magnetic field.It was found that there were at most 6 peaks in a 1H NMR spectrum when the external magnetic field was in its be plane, and 5 peaks in ah and ac planes. Combined with the computer calculations of NMR spectrum, the results indicate that the hydrogen atoms in KB5 are in the form of hydroxyl and water groups. The O-H distances in the hydroxyl groups are 0.1005±0.001 nm and 0.1054±0.001 nm. The O-H distances in the water groups are 0.0983±0.001nm and 0.0968±0.0001nm with H-O-H angle of 108±1°.These show that the proton position data obtained by X-ray diffraction are far from our values,and the data by neutron diffraction are more close to our values.

关 键 词：五氧硼酸钾 晶体结构 NMR 

分 类 号：O614.113[理学—无机化学]