Reference

Crystal chemistry of natural zeolites of the natrolite group

Crystal chemistry of natural zeolites of the natrolite group. Pechar, Frantisek (Ustav Geol. Geotech., CSAV, Prague, Czech.). Acta Mont., 62, 75-84 (Czech) 1983. CODEN: ACMTCX. ISSN: 0365-1398. DOCUMENT TYPE: Journal CA Section: 53 (Mineralogical and Geological Chemistry) Fundamental crystal-chem. 1319-20-6 and 12399-54-1 which are cas registry numbers are also used here. parameters of natrolite [1318-95-2], mesolite [12043-66-2], scolecite [1319-20-6], and thomsonite [12399-54-1] were detd. to investigate the interdependences between chem. compn. and structural symmetry and between major element contents (Si, Al, Na, and Ca) and the unit cell dimensions. Results are presented in terms of correlation coeffs. and suggest the possibility of classifying zeolites on the basis of the group-subgroup theory of J. Neubuesser and H. Wondratschek (1966). .

Natrolite: refinement of the crystal structure of two samples from Marienberg (Usti nad Labem, CSSR)

Natrolite: refinement of the crystal structure of two samples from Marienberg (Usti nad Labem, CSSR). Kirfel, A.; Orthen, M.; Will, G. (Mineral. Inst., Univ. Bonn, Bonn D-5300/1, Fed. Rep. Ger. 1318-95-2 is the cas registry number. This chemical is also mentioned in this article.). Zeolites, 4(2), 140-6 (English) 1984. CODEN: ZEOLD3. ISSN: 0144-2449. DOCUMENT TYPE: Journal CA Section: 53 (Mineralogical and Geological Chemistry) Natrolite [1318-95-2] from Marienberg is orthorhombic with space group Fdd2. Accurate crystal structure analyses by single crystal x-ray diffractometry were performed on 2 natrolite specimens (a0 = 18.285 (18.296), b0 = 18.630 (18.647), and c0 = 6.585 (6,585) ?, from the same locality but with different origins. The (b0 - a0) differences of 0.345 and 0.351 ?, resp., indicate fully ordered Al-Si distributions. The refinements of the structures by least squares calcns. yielded agreement factors of 0.018 and 0.030, resp. The refined at. positional parameters agree within the limits of tolerance. The H atoms could be located unambiguously from electron d. difference syntheses. .