Monoclinic Pyrrhotite

NEW OBSERVATIONS ON NATURAL PYRRIIOTITES Part IL Lamellar Magnetite in Monoclinic Pyrrhotite

Monoclinic pyrrhotite from Norseman, Western Austra"lia, has lamellae of submicrometer thickness, identified by microprobe and electron diffraction as magnetite. The lamella zurface is (111) of magnetite parallel to (001) of pyrrhotite, corresponding to a close fit of close-packed planes of the two structures' The perfect lamellar nature of the magnetite in unaltered pyrrhotite indicates origin...

Dicyclo­hexyl­ammonium thio­cyanate: monoclinic polymorph

The title salt, C(12)H(24)N(+)·NCS(-), represents a monoclinic polymorph of the previously reported ortho-rhom-bic form [Khawar Rauf et al. (2008 ▶). Acta Cryst. E64, o366]. Two independent formula units comprise the asymmetric unit with the major difference in their mol-ecular structures relating to the relative dispositions of the cyclo-hexyl rings [dihedral angles = 79.88 (6) and 67.72 (5)°]...

Microstructure of a Pyrrhotite-pentlandite Intergrowth in Ll6 Saint-séverin

2-Pyridone: monoclinic polymorph

The asymmetric unit in the title compound, C(5)H(5)NO, comprises two independent but virtually identical mol-ecules of 2-pyridone, and represents a monoclinic polymorph of the previously reported ortho-rhom-bic (P2(1)2(1)2(1)) form [Penfold (1953 ▶). Acta Cryst.6, 591-600; Ohms et al. (1984 ▶). Z. Kristallogr.169, 185-200; Yang & Craven (1998 ▶). Acta Cryst. B54, 912-920]. The independent mol-e...

Natural Pyrrhotite as a Catalyst in Prebiotic Chemical Evolution

The idea of an autotrophic organism as the first living being on Earth leads to the hypothesis of a protometabolic, complex chemical system. In one of the main hypotheses, the first metabolic systems emerged from the interaction between sulfide minerals and/or soluble iron-sulfide complexes and fluids rich in inorganic precursors, which are reduced and derived from crustal or mantle activity. W...