Monoclinic crystal

Solid cellulose forms a microcrystalline structure with regions of high order, i.e., crystalline regions, and regions of low order that are amorphous. Naturally occurring cellulose (cellulose I) crystallizes monoclinic sphenodic. The molecular chains lay in the fiber direction ... 

Anthracenophane (44), first described by Golden 68>, is an orange-colored compound that crystallizes monoclinically. 

Beta-sulfur is pale-yellow, opaque needle-like crystals monoclinic structure brittle stable between 94.5 to 120°C converts to orthorhombic form on standing density 1.96 g/cm melts at 115.2°C. 

In the following Table 27 two compounds, NaCuFs (271) and NaCrFs (316), both distorted by the Jahn-Teller effect, have been listed also. They are isostructural with each other and crystallize monoclinicly, but are closely related to the GdFeOs-type. Probably the Jahn-Teller distortion elongates the MeFe-octahedra, as stated in the corresponding compounds Na2MeF4 (page 35). 

Monoclinic. The essential symmetry for this class is one proper or improper twofold axis, that.is, either 2 or m (s2). This guarantees that one axis is perpendicular to the plane defined by the other two. It is important to appreciate that the mere occurrence of an axis that appears to be perpendicular (to within whatever accuracy, however great) does not make the crystal monoclinic. The perpendicularity must be the rigorous result of the symmetry,... 

The optical band gap of SI (4.3 eV) is larger than the simulated band gap (3.9 eV) of Hf02 (CN 7.0). The inherent error for the band gap calculation using DFT method is considered as reason about the difference (0.4 eV) between the optical band gap and the simulated band gap. However, the difference (1.7eV) between the optical (3.98 eV) and simulated band gap (2.28 eV) of S2 is larger than that of SI. Considering the difference (0.8 eV) between the optical band gap and the simulated band gap of the crystallized monoclinic hafnium oxide with the thickness of 900 nm, the transition rate for the optical absorption is suggested as another reason for the band gap difference of S2. 

Ferrous ammonium sulphate or Mohr s salt, FeS04.(NH4)2S04. 6H20, may be prepared by adding a saturated solution of ammonium sulphate at 40° C. to the requisite quantity of ferrous sulphate dissolved also at 40° C. in the smallest amount of water. The solution, on cooling, deposits an abundant crop of pale green crystals, monoclinic,3 and of density 1 864 at 20° C. The salt is kept dry by pressure between filter papers. 

BiJB20J = 81403(803)2] crystallizes monoclinic (P2,/c = with isolated BOf- groups... 

The silica-free zirconium hydrous oxide gives no crystallization peak in DTA-TG measurement. XRD analysis (Fig. 4) shows that the pure zirconium hydrous oxide dried at 110°C is in a well-crystallized monoclinic state with small amount of tetragonal phase. Obviously, the existence of silica... 

FIGURE 15.5 Variation in crystal morphology for identical unit cells, (a) Crystals in the rhombohedral system that only have faces present in the unit cell (001), (010), and (100). (b) Cubic system the leftmost picture is a cube, the rightmost one a regular octahedron in between are intermediate shapes, (c) Examples of the various shapes that an ot-lactose monohydrate crystal (monoclinic) can assume in practice. In (a) and (b) the shapes are shown in perspective. In (c) we have projections (all in the same direction with respect to the axes of the unit cell). 

Fig. 3.9a and b. CP-MAS- C NMR spectra of cyclohexanonacontane at different temperatures for a solution crystallized, monoclinic crystals and b melt crystallize, orthorbcmlac crystals. Curves from Ref. 

Formula weight 522.26. Well-formed, transparent yellow crystals, monoclinic prismatic d 2.773. Sparingly soluble in water insoluble in alcohol and ether may be recrystallized without decomposition from aqueous (NH4)sC03. 

Chiral Sp with twist axis normal to the layers. Three-dimensional crystal, C-centred monoclinic (a > b). Three-dimensional crystal, monoclinic (a > b), herringbone structure. ... 

There are several reports " on the inelusion compounds of CDCA, despite many articles on those of DCA and CA. It is known that CDCA forms guest-free crystals (monoclinic as well as inclusion crystals with... 

It is not only the crystallization rate, however, which is influenced by nucleating agents, but also the morphology. Isotactic poly(propylene) crystallizes monoclinically in the presence of / -/-butyl benzoic acid and pseudohexagonally when the quinacridone dyestuff. Permanent Red EBB, is added. 

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