A new type of char
ge orderin
g stable up to
T1 ![](/ima<font color=)
ges/entities/ap.
gif"> 500 K has been evidenced by electronmicroscopy in the Mn
3+-rich perovskite Bi
2/3Sr
1/3MnO
3. This new superstructure, based ona
Imma-type subcell is characterized by a double modulation with
a = 2ap![](/isubscribe/journals/cmatex/15/i02/eqn/cm021309fe10001.<font color=)
gif">,
b = 4
ap,
c =
ap![](/isubscribe/journals/cmatex/15/i02/eqn/cm021309fe10002.<font color=)
gif">. X-ray powder diffraction evidences a second structural transition at
T2 ![](/ima<font color=)
ges/entities/ap.
gif"> 580 K andsu
ggests a displacive modulation of the oxy
gen atoms below
T2. These results are interpretedas the correlated coexistence of char
ge-orbital orderin
g and modulated displacive orderin
gof oxy
gen atoms, in the form of double Mn stripes, below 500 K.