Study on mineral structural stability of marine 1nm manganate

In order to study the phase transformation between 1nm manganate and 0.7nm mangenate, a series of Slnm Me²⁺ tnanganates were made after the synthetic lnm Na⁺ manganate substituted with different kinds of divalent rations.The X-ray diffraction analysis of wet Slnm Me²⁺ manganates after 24 h room temperature dry showed that their basal d-spacing had been changed, indicating that there was phase transformation between lnm and 0.7nm manganates.Those 1nm tnanganates with unstable structure rnllapsed into 0.7nm manganate by losing one interlayer OH-H₂O, while those with stable structure still retained the 1nm d-spacing.This factor reminds us that the manganese nodule samples must be kept in wet condition to avoid the misleading results.The structural stability of lnm manganate is mainly controlled by the interlayer divalent rations.There is a possitive correlation between the amount of rations in the interlayer and the structural stability, while the capacity of different rations in stabilizing the structure of 1nm manganate is as follows:
Ni > Cu > Co > Zn > Ca > Mg > Na.