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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．
1HNMR room temperature spectra of potassium pentaborate (KB5) single crystals with different orientations relative to the external magnetic field are given. It is found that when the external magnetic field in the crystal bc plane, 1HNMR spectrum up to 6 peaks. In the ah or ac plane, up to only 5 peaks. Fitting the computer with NMR spectroscopy showed that in potassium pentaborate, the hydrogen atoms are in the form of hydroxyl and water molecules. In the hydroxyl group, O-H distances were 0.1005 ± 0.001 nm and 0.1054 ± 0.001 nm, whereas in water molecules, the O-H distances were 0.0983 ± 0.001 nm and 0.0968 ± 0.001 nm, and the angle of H-O-H is 108 ° ± 1 °. These show that the data in this paper are similar to the neutron diffraction results and the data of the proton positions obtained by X-ray diffraction are far from our results.