  A-site ordered manganites LnBaMn1.96Fe0.04O5 and LnBaMn1.96Fe0.04O6 are
investigated by x-ray full-profile diffraction and Moessbauer spectroscopy.
Powder samples were oriented with preferred orientation of platy crystallites
in the plane of sample surface. March-Dollase function of preferred orientation
was employed in analysing both the Rietveld patterns and the Mossbauer spectra.
Combined effects of preffered orientation and vibrational anisotropy on the
line area asymmetry of Mossbauer doublet are analysed. Constructive and
destructive interference between the effects of texture and vibrational
anisotropy is observed in LnBaMn1.96Fe0.04O6 and LnBaMn1.96Fe0.04O5,
respectively. Both series of the manganites show the main axis of electric
field gradient perpendicular to layers (Vzz along c) with Vzz>0 in oxygen-poor
series and Vzz<0 in oxygen-rich series. Charge-orbital order (COO) melting
around Fe dopants explains the single-site spectra observed for several Ln in
both "O5" and "O6" series, except LaBaMn1.96Fe0.04O5. However, the short-range
COO persists to be observed in magnetization and in Rietveld patterns.
