Dispersed excitation spectroscopy, recorded through a spectrometer use
d as a narrowband filter, made it possible to obtain the rotational an
alysis of weak blended transitions of NiF. Five electronic transitions
, involving a common upper state and five lower states, have been obse
rved in the visible region. One of these transitions (17 529.5 cm(-1))
has been rotationally analyzed. Both the energy splittings between th
e five new low-lying states and the value of the rotational constant o
f the lower state of the transition analyzed (B = 0.38511 cm(-1)) are
evidence that these states are not the already known five lower double
t states. Another transition (18 348 cm(-1)) involving the ground (2)
Pi(3/2) state of NiF has been partially analyzed. The upper state (B'
= 0.3702 cm(-1)) is also linked to the lower (2) Sigma states but not
to the components of the (2) Delta state, ruling out a (2) Pi(1/2) ass
ignment for this upper state. All these results suggest that the new o
bserved states could be components of quartet states. (C) 1997 Academi
c Press.