  We infer the gas kinematics, diagnostics and ionic radial profiles, distance
and central star parameters, nebular photo- ionization model, spatial structure
and evolutionary phase of the PN NGC 6741 by means of long-slit high-resolution
spectra at nine position angles. NGC 6741 (distance ~2.0 kpc, age ~1400 yr,
ionized mass Mion ~0.06 Mo) is a dense (electron density up to 12,000 cm^(-3)),
high-excitation, almost- prolate ellipsoid, surrounded by a sharp
low-excitation skin (the ionization front), and embedded into a spherical
(radius ~ 0.080 pc), almost-neutral, high-density (n(HI) ~7 x 10^3 atoms
cm^(-3)) halo containing a large fraction of the nebular mass (Mhalo>0.20 Mo).
The kinematics, physical conditions and ionic structure indicate that NGC 6741
is in a deep recombination phase, started about 200 years ago, and caused by
the quick luminosity drop of the massive (M*=0.66-0.68 Mo), hot (logT* ~ 5.23)
and faint (log L*/Lo ~ 2.75) post--AGB star, which has exhausted the
hydrogen-shell nuclear burning and is moving along the white dwarf cooling
sequence. The general expansion law of the ionized gas in NGC 6741, Vexp (km
s^(-1)=13 x R", fails in the innermost, highest-excitation layers, which move
slower than expected. The observed deceleration is ascribable to the luminosity
drop of the central star, and appears in striking contrast to recent reports
inferring that acceleration is a common property of the Planetary Nebulae
innermost layers. Some general implications on the shaping mechanisms of
Planetary Nebulae are discussed.
