|
|
 |
|||||||||||||||||
|
|||||||||||||||||
 |
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Universita di Modena, Dipartimento di Scienze della Terra, Modena, Italy
Phengitic muscovite-2M 1 crystals [ (super [12]) (K (sub 0.88-0.99) Na (sub 0.01-0.09) Ca (sub 0.00-0.06) Ba (sub 0.00-0.01) ) (super [6]) (Al (sub 1.64-1.88) Fe (super 2+) (sub 0.06-0.29) Fe (super 3+) (sub 0.01-0.16) Mg (sub 0.00-0.16) Mn (sub 0.00-0.07) Ti (sub 0.00-0.06) ) (super [4]) (Si (sub 2.87-3.30) Al (sub 0.70-1.13) )(OH) (sub 1.56-2.07) F (sub 0.00-0.41) O (sub 9.91-10.25) ] from pegmatites and peraluminous granites were refined to investigate the influence of phengitic substitution on the mica structure. Single-crystal X-ray diffraction data were collected for eleven crystals in the C2/c space-group (agreement factor 2.1% < or = R obs , < or =3.9%). Tetrahedral Si and Al cation disorder was found for each sample, with the mean tetrahedral cation-oxygen distances ranging from 1.639 Aa < or ={T1-O}< or =1.647 Aa and 1.640 Aa < or ={T2-O}< or =1.646 Aa. As phengitic substitution increases, the octahedral sheet expands and requires a less distorted (more hexagonal) tetrahedral ring (7.70 degrees < or =alpha < or =11.38 degrees ) and low corrugation of the basal O plane (0.1796 Aa< or =Delta Z< or =0.2296 Aa). The electron density at the M2 site is greater than that required for the ideal muscovite-2M 1 structure, and a small excess of electron density is found in the M1 site. The inner sixfold coordination of the interlayer (A) cation is elongated along c (super *) , which is consistent with the high alpha values and the long A-O11 bond length.
This record provided courtesy of AGI/GeoRef.
This article has been cited by other articles:
|
|
 |
|
  M.F. Brigatti, C.V. Guidotti, D. Malferrari, and F.P. Sassi Single-crystal X-ray studies of trioctahedral micas coexisting with dioctahedral micas in metamorphic sequences from western Maine American Mineralogist, February 1, 2008; 93(2-3): 396 - 408. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Cibin, G. Cinque, A. Marcelli, A. Mottana, and R. Sassi The octahedral sheet of metamorphic 2M1-phengites: A combined EMPA and AXANES study American Mineralogist, February 1, 2008; 93(2-3): 414 - 425. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Curetti, G. Ferraris, and G. Ivaldi Correlation between crystallization pressure and structural parameters of phengites American Mineralogist, February 1, 2008; 93(2-3): 451 - 455. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Kameda, R. Miyawaki, V. A. Drits, and T. Kogure POLYTYPE AND MORPHOLOGICAL ANALYSES OF GUMBELITE, A FIBROUS Mg-RICH ILLITE Clays and Clay Minerals, October 1, 2007; 55(5): 453 - 466. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Kogure Imaging of dioctahedral 2:1 layers by high-resolution transmission electron microscopy (HRTEM): Possibility of recording the dehydroxylate American Mineralogist, August 1, 2007; 92(8-9): 1368 - 1373. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Ma and G. R. Rossman Ganterite, the barium mica Ba0.5K0.5Al2(Al1.5Si2.5)O10(OH)2, from Oreana, Nevada American Mineralogist, April 1, 2006; 91(4): 702 - 705. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. Brigatti, D. Malferrari, M. Poppi, and L. Poppi THE 2M1 DIOCTAHEDRAL MICA POLYTYPE: A CRYSTAL CHEMICAL STUDY Clays and Clay Minerals, April 1, 2005; 53(2): 190 - 197. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. A. DRITS and B. A. SAKHAROV Potential problems in the interpretation of powder X-ray diffraction patterns from fine-dispersed 2M1 and 3T dioctahedral micas European Journal of Mineralogy, February 1, 2004; 16(1): 99 - 110. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. Brigatti, M. F. Brigatti, E. Caprilli, M. Marchesini, and L. Poppi THE CRYSTAL STRUCTURE OF ROSCOELITE-1M Clays and Clay Minerals, June 1, 2003; 51(3): 301 - 308. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. BENINCASA, M. F. BRIGATTI, L. POPPI, and F. B. BARREDO Crystal chemistry of dioctahedral micas from peraluminous granites: the Pedrobernardo pluton (Central Spain) European Journal of Mineralogy, June 1, 2003; 15(3): 543 - 550. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. R. Peacor, D. R. Peacor, B. Bauluz, H. Dong, D. Tillick, and Y. Yan TRANSMISSION AND ANALYTICAL ELECTRON MICROSCOPY EVIDENCE FOR HIGH Mg CONTENTS OF 1M ILLITE: ABSENCE OF 1M POLYTYPISM IN NORMAL PROGRADE DIAGENETIC SEQUENCES OF PELITIC ROCKS Clays and Clay Minerals, December 1, 2002; 50(6): 757 - 765. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. PAVESE, G. FERRARIS, V. PISCHEDDA, and F. FAUTH M1-site occupancy in 3T and 2M1 phengites by low temperature neutron powder diffraction: reality or artefact? European Journal of Mineralogy, December 1, 2001; 13(6): 1071 - 1078. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. F. Brigatti, D. E. Kile, and M. Poppi CRYSTAL STRUCTURE AND CRYSTAL CHEMISTRY OF LITHIUM-BEARING MUSCOVITE-2M1 Can Mineral, August 1, 2001; 39(4): 1171 - 1180. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. BRIGATTI, E. GALLI, L. MEDICI, L. POPPI, G. CIBIN, A. MARCELLI, and A. MOTTANA Chromium-containing muscovite: crystal chemistry and XANES spectroscopy European Journal of Mineralogy, April 1, 2001; 13(2): 377 - 389. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. Brigatti, C. Lugli, L. Poppi, E. E. Foord, and D. E. Kile Crystal chemical variations in Li- and Fe-rich micas from Pikes Peak batholith (central Colorado) American Mineralogist, September 1, 2000; 85(9): 1275 - 1286. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. F. Brigatti, P. Frigieri, C. Ghezzo, and L. Poppi Crystal chemistry of Al-rich biotites coexisting with muscovites in peraluminous granites American Mineralogist, March 1, 2000; 85(3-4): 436 - 448. [Abstract] [Full Text] [PDF]
|
|
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
