Eleven homoionic montmorillonites were subjected to form complexes with an amine possesing two aromatic rings of chloroaniline type connected through a central methylene bridge in a bent form. The amine is 4, 4'-methylene-bis-(2-chloroaniline). The complexes obtained showed various noticeable features depending on preparation ways and interlamellar ion species, as in the following:(1) the complexes resulted by immersing montmorillonites saturated with H⁺, Ca²⁺, Sr²⁺, Mg²⁺, Zn²⁺, Cd²⁺, Mn²⁺, Fe³⁺, Cu²⁺, Co²⁺ and Ni²⁺ in acetone solution of the amine respectively gave 14-15A of d (001) and almost same light reddish purple colors, indifferently with respect to the ion species;(2) in contrast to (1), complexes made by immersing the same montmorillonites in a melt of the amine at ca. 140°C do show marked differences in the features suggesting the formation of different assemblages between the clay sheets, viz. only four montmorillonites saturated with Mn²⁺, Fe³⁺, Co²⁺ and Cu²⁺ can yield complexes which give rise to the basal spacing of at least 20 Å and show their own colors (dark carmine, brown, dark reddish brown and black corresponding the employment of Mn²⁺, Fe³⁺, Co²⁺ and Cu²⁺ respectively), whereas, other substitution clays formed complexes which give 14-15Å of d (001), similarly as the case of (1), however, their colors were not the light but dull brown mostly.
Here, it is noted that the four ion species as mentioned above are transition metal ions having odd number electrons in their d-shell without exception, and that the magnitude of the interlayer clearance in the long-periodicity complexes can agree with approximately a long-axis spacing of the amine molecule and twice of the short-axis spacing.
Then, the assemblage configurations between the sheets were conjectured in the light of the X-ray data and pronounced inactive properties of the amine per se for oxydations and for solutional complex formations with all ions used.
Here, concerning the conjectures, the present authors are possesed with a perceiving that interactions of the amine-aromatic π electron for the metallic ions in wide meanings, might sensibly be taken into account. And in this, not only the π electron coordination but also the electro-static interactions between the organic molecule and the cations should be worth considerations particularly when it was thought that the rather high temperature of the amine-melt did effectively removed interlayer hydration water, and consequently that electric fields between the cations and clay sheets of negatively charged should draw the ring π electron toward the. mid-way position cations.

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Eleven homoionic montmorillonites were subjected to form complexes with an amine possesing two aromatic rings of chloroaniline type connected through a central methylene bridge in a bent form. The amine is 4, 4'-methylene-bis-(2-chloroaniline). The complexes obtained showed various noticeable features depending on preparation ways and interlamellar ion species, as in the following:(1) the complexes resulted by immersing montmorillonites saturated with H⁺, Ca²⁺, Sr²⁺, Mg²⁺, Zn²⁺, Cd²⁺, Mn²⁺, Fe³⁺, Cu²⁺, Co²⁺ and Ni²⁺ in acetone solution of the amine respectively gave 14-15A of d (001) and almost same light reddish purple colors, indifferently with respect to the ion species;(2) in contrast to (1), complexes made by immersing the same montmorillonites in a melt of the amine at ca. 140°C do show marked differences in the features suggesting the formation of different assemblages between the clay sheets, viz. only four montmorillonites saturated with Mn²⁺, Fe³⁺, Co²⁺ and Cu²⁺ can yield complexes which give rise to the basal spacing of at least 20 Å and show their own colors (dark carmine, brown, dark reddish brown and black corresponding the employment of Mn²⁺, Fe³⁺, Co²⁺ and Cu²⁺ respectively), whereas, other substitution clays formed complexes which give 14-15Å of d (001), similarly as the case of (1), however, their colors were not the light but dull brown mostly.
Here, it is noted that the four ion species as mentioned above are transition metal ions having odd number electrons in their d-shell without exception, and that the magnitude of the interlayer clearance in the long-periodicity complexes can agree with approximately a long-axis spacing of the amine molecule and twice of the short-axis spacing.
Then, the assemblage configurations between the sheets were conjectured in the light of the X-ray data and pronounced inactive properties of the amine per se for oxydations and for solutional complex formations with all ions used.
Here, concerning the conjectures, the present authors are possesed with a perceiving that interactions of the amine-aromatic π electron for the metallic ions in wide meanings, might sensibly be taken into account. And in this, not only the π electron coordination but also the electro-static interactions between the organic molecule and the cations should be worth considerations particularly when it was thought that the rather high temperature of the amine-melt did effectively removed interlayer hydration water, and consequently that electric fields between the cations and clay sheets of negatively charged should draw the ring π electron toward the. mid-way position cations.

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In order to investigate the genesis of stevensite and “hydrated talc” experimentally, natural and synthetic xonotlite were treated hydrothermally with MgCl₂ solution for temperatures ranging from 100°C to 450°C. The products were examined by means of X-ray diffraction, thermal analysis, infrared absorption spectroscopy and electron microscopy.
Both natural and synthetic xonotlite alter to “hydrated talc”+ chrysotile (200-400°C) and then talc + chrysotile (≥450°C). Below 150°C is formed the poorly crystallized silicate having a trioctahedral layer structure. The formation of stevensite covld not be recognized under the present experimental conditions. However, it is worthy to note that the phase having the expandable layer was obtained by treatment with 1N MgCl₂solution in the temperature range from 300°C to 400°C.
Some considerations have been made on the mechanism of the conversion of both natural and synthetic xonotlite into phyllosilicate.

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