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分别以氯化镁和氮化镁作为起始物料，在低温（25～90℃）溶液中采用化学方法合成水镁石．然后分别测定水镁石和水的氢同位素组成，得到水镁石-水体系的氢同位素分馏方程为：103lna=－4．88×106／T2－22．54。由于矿物-水体系氢同位素分馏的压力效应，本研究通过大气压力下的实验得到的分馏系数值，系统地低于根据高温（510～100℃）高压（100～103MPa）热液交换实验结果向低温方向外推获得的分馏系数值。与已知的其它含羟基矿物-水体系低温氢同位素分馏曲线比较的结果表明，在热力学平衡条件下，水镁石相对于高岭石和伊利石／蒙脱石亏损D，但相对于外铁矿富集D。因此，合羟基矿物存在如下D富集顺序：Al－OH＞Mg－OH＞Fe－OH。
Magnesium chloride and magnesium nitride as the starting material, respectively, in the low temperature (25 ~ 90 ℃) solution by chemical synthesis of brucite. Then the hydrogen isotope compositions of brucite and water were respectively determined. The hydrogen isotope fractionation equation of brucite-water system was obtained as follows: 103lna = -4.88 × 106 / T2-22.54. Due to the pressure effect of hydrogen isotope fractionation in mineral-water system, the fractional distillation coefficient obtained by experiments under atmospheric pressure is systematically lower than the experimental results of hydrothermal exchange based on high pressure (100 ~ 103 MPa) at high temperature (510 ~ 100 ℃) Fractional fractional values obtained by extrapolation in the cryogenic direction. Compared with the low-temperature hydrogen isotope fractionation curves of other known hydroxyl-bearing mineral-water systems, the results show that brucite has a loss D relative to kaolinite and illite / montmorillonite under thermodynamic equilibrium conditions. However, Enrichment Therefore, there is the following order of D enrichment for hydroxy-mineral: Al-OH> Mg-OH> Fe-OH.