Synthesis of Anhydrous Na-fluor-hectorite [Na1/3Mg2(2/3)Li1/3(Si4O10)F2] and Its Swelling Characteristics with Water

Synthesisof anhydrous Na-Huor-hectorite[Na1/3Mg2(2/3)(Si4O10)F2](1)was undertaken and its formation was confirmed. It was found that the swelling inclinations of(1)are Iarger than those of Na-taenio1ite(NaMg2Li(Si4O10)F2)(2). The three-layer hydrated state, 18.82A phase, is observed for(1)and so-called indefinite swelling seems to occuL It seems that such larger hydration properties of (1)can be attributed to the decrease of layer charge and the increase of interlayer vacancies. It is also found that the interlayer Na ions in(1)are base exchangeable.