ON THE EXISTENCE OF LOWER HYDRATES OF M(OH)X(M IS SR, BA, X IS CL, BR, I)

Preparation of the lower hydrates of M(OH)X(M is Ba, Sr; X is Cl, Br, I) was attempted both by dehydration experiments of Ba(OH)X . 2H(2)O ( X is Cl, Br), Ba(OH)I . 4H(2)O, and Sr(OH)X . 4H(2)O (X is Cl, Br), an d by rehydration of the anhydrous salts using infrared, Raman, and hig h-temperature Raman spectroscopic methods. Thus, the hitherto unknown compound Ba(OH)I . 2H(2)O has been established and Ba(OH)Cl . 0.5H(2)O , but not Ba(OH)Br . 0.5H(2)O, has been confirmed. Ba(OH)I . 0.5H(2)O and lower hydrates of Sr(OH)X were not obtained. Ba(OH)I . 2H(2)O is i sostructural with Ba(OH)X . 2H(2)O (X is Cl, Br). The crystal structur e of Ba(OH)Cl . 0.5H(2)O is not known so far. The dehydration and fusi ng temperatures of M(OH)X . 4H(2)O and M (OH)X, respectively, are pres ented.