A preferred orientation correction to describe a fiber texture under glancing incidence

Simeone, D.; Gosset, D.; Baldinozzi, G.

doi:10.1107/S0021889812045736

Figure 2
Description of the scattering vector and the preferred orientation vector in the sample frame. The scattering plane appears in gray in the figure. The preferred orientation vector $[[\bf{HKL}]]$ is defined by the azimuthal and polar angles $[\varphi]$ and $[\chi]$ , respectively, in the $[{\bf X}_{\rm S}{\bf Y}_{\rm S}{\bf Z}_{\rm S}]$ frame. In asymmetric coplanar diffraction conditions, the scattering vector $[{\bf q}_{hkl}}]$ is not parallel to $[{\bf Z}_{\rm S}}]$ . In glancing incidence, the scattering vector does not possess a component along $[{\bf X}_{\rm S}}]$ . In grazing incidence, this component is non-null. The angle between $[{\bf q}_{hkl}}]$ and $[[\bf{HKL}]]$ is denoted by $[\rho]$ in this frame.