International
Tables for
Crystallography
Volume B
Reciprocal space
Edited by U. Shmueli

International Tables for Crystallography (2006). Vol. B, ch. 4.4, p. 459   | 1 | 2 |

Figure 4.4.4.4 

P. S. Pershana*

aDivision of Engineering and Applied Science and The Physics Department, Harvard University, Cambridge, MA 02138, USA
Correspondence e-mail: pershan@deas.harvard.edu

[Figure 4.4.4.4]
Figure 4.4.4.4

Scattering intensities in reciprocal space from three-dimensional tilted hexatic phases: (a) the smectic-I and (b) the smectic-F. The variation of the intensity along the [Q_{L}] direction indicates interlayer correlations that are absent in Figs. 4.4.4.1(d)[link] and (e)[link]. The peak widths [\Delta {\bf Q}_{L1,2}] and [\Delta {\bf Q}_{H1,2}] correspond to the four inequivalent widths in the smectic-F phase. Similar inequivalent widths exist for the smectic-I phase. The circle through the shaded points in (a) indicates the reciprocal-space scan that directly measures the hexatic order. A similar scan in the smectic-C phase would have intensity independent of [\chi].