The spectroscopic and photophysical properties of zeolite-Y-entrapped [Ru(
bpy)
3]
2+ co-doped with either[Fe(
bpy)
3]
2+ or [Fe(tpy)
2]
2+ over a ran
ge of iron complex loadin
gs are presented. In solution, [Ru(
bpy)
3]
2+under
goes efficient
bimolecular ener
gy transfer to [Fe(
bpy)
3]
2+, whereas only radiative or trivial ener
gy transferoccurs
between [Ru(
bpy)
3]
2+ and [Fe(tpy)
2]
2+. In sharp contrast, within zeolite Y,
both [Fe(
bpy)
3]
2+ and [Fe(tpy)
2]
2+ were found to effectively quench the donor emission. Fittin
g the Perrin model to the photophysicaldata yields an effective quenchin
g radius of 32 and 27 &Arin
g;, respectively, for [Fe(
bpy)
3]
2+ and [Fe(tpy)
2]
2+. Thelon
g-ran
ge nature of the quenchin
g su
ggests F&
ouml;rster ener
gy transfer. Detailed spectroscopic investi
gationsindicate that [Fe(tpy)
2]
2+ bound within zeolite Y under
goes si
gnificant distortion from octahedral
geometry.This distortion results in increased oscillator stren
gth and enhanced spectral overlap,
between the [Ru(
bpy)
3]
2+3d
![](/ima<font color=)
ges/
gifchars/pi.
gif" BORDER=0 >-
![](/ima<font color=)
ges/
gifchars/pi.
gif" BORDER=0 >* donor emission and the co-incident acceptor
1T2-
1A1 li
gand field a
bsorption compared with solution.This turns on an efficient ener
gy transfer to [Fe(tpy)
2]
2+ within the confinement of the zeolite Y superca
ge.Overall, this is an interestin
g example of the a
bility of the zeolite environment to provoke new photophysicalprocesses not possi
ble in solution.