Crystallographic Cells

Each record in this category can appear only once in a PDB file and it occupies exactly one line. Examples of such records arc HEADER - the starting record of each PDB file discussed in detail below, END - the last (terminating) record, and CRYSTl - describing the crystallographic cell. 

Figure 11.16 Schematic orientation of the planar FePc molecules in the crystallographic cell (a) a-FePc calculated from the data obtained by Ballirano and co-workers [Ballirano et al., 1998] (b) /3-FePc calculated from the data obtained by Kimer and co-workers [Kimer et al., 1976],...

Figure 3 Crystallographic cell dimensions and symmetries for the BaPb1.xBixOs solid solution at 300K, from reference 18.

Figure 6 Crystallographic cell parameters and symmetries at 300K for the Ba K BiOg solid solution re-plotted from reference 59.

There are cases in which the number of repeat units in the crystallographic cell may be three or one. For the cases where it is three, Z will be divisible by three. For example, for TiS, - R3m (No. 166),... 

Z = number of molecules in the primitive cell Z(number of molecules in crystallographic cell) repeat units in cell... 

Table 3.1 Crystallographic cell constants for the two polymorphic forms of 3-XXIV...

The triple sulphates NaMgMm(S04)3, where Mm = Al, Ga, or In, have been prepared by thermal syntheses, and crystallographic cell parameters reported for all of them.409... 

Figure 14. The variation in crystallographic cell parameters for the series (a)...

If r t) is the time dependent atomic position vector, taken with respect to the origin of the crystallographic cell, it can be expressed as the sum of two terms, the molecular centre of mass, this is a time dependent vector, (0ext> that allows a description of the vibrations of the crystal, the phonons. The second term is the position vector of the atom, H(0int, given by a Cartesian coordinate system with its origin at the molecular centre of mass. 

The X-ray diffraction patterns show the presence of the hydrotalcite-like structure in all the dried Mg-Fe and Mg-Al samples. Figure 1 reports the X-ray diffraction patterns of Mg/Fe=2.0, Mg/Al=2.0 and MgO samples after calcination. The patterns of the calcined Mg-Fe and Mg-Al samples correspond to that of a poorly crystallized MgO. The shift of the main reflections in the Mg/Al sample towards higher 20 values with respect to MgO is due to the decrease in the volume of the crystallographic cell of MgO (periclase), in agreement with an isomorphic replacement of Mg " cations with the smaller Af cations (Mg " = 0.65 A Ar =... 

Structure type Prototype for the structural arrangement of the crystallographic cell. 

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