thaumasite การใช้

• Upon analyzing the structure of both ettringite and thaumasite, it was deduced that both minerals have hexagonal structures, but different space groups.
• Further X-ray studies ensued; namely Wellin ( 1956 ) which determined the crystal structure of thaumasite, and Besjak & Jelenic ( 1966 ) which gave affirmation of the structure nature of ettringite.
• Ettringite crystals have a P31c with a = 11.224 ? c = 21, 108 ? while thaumasite crystals fall into space group P6 3 with a = 11.04 ? c = 10.39 ?
• In contrast, thaumasite consists of a cylindrical column of Ca 3 [ Si ( OH ) 6 ?2H 2 O ] 3 + in the " c " axis, with sulfate and carbonate anions in channels between these columns which contain water molecules as well.
• Differences between structures of ettringite and thaumasite arise from the columns of cations and anions : Ettringite cation columns are composed of Ca 3 [ Al ( OH ) 6 ?2H 2 O ] 3 +, which run parallel to the " c " axis, and the other columns of sulfate anions and water molecules in channels parallel to these columns.