Rhenium(I) diimine complexes (Cont.)
Re–Re, Re–M, and Re–C bond
homolysis reactions
irradiation, 148
photoirradiation, 147– 148
Ruthenium(II)–Rhenium(I)
supramolecular photocatalyst,
178 – 180
solar energy, 168
uses, 139
weak interactions, effects
bathochromic and hypsochromic
shifts, 146
phosphine ligands, 144– 145
photochemical ligand
substitution reaction, 144
UV/Vis absorption and emission
spectra, 144f
Rhenium(I) diimine complex
photocatalyst
light-harvesting system, periodic
mesoporous organosilica,
180 – 181
mononuclear
gas–solid state reactions, 171
one-electron reduced (OER)
species, 169– 170
sacrificial reductant, 168
multicomponent systems
drawback, 177– 178
role, 176– 177
reaction mechanism
CO 2 adduct, 175
OER species, 173
ruthenium(II)–rhenium(I)
supramolecular, 178– 180
Rhenium(I) diimine complex
photochemistry
fac-Re(bpy)(CO) 3 Cl, higher excited
states
irradiation, 163– 165
linear-shaped Re(I) oligomers
and polymers, 163f
photochemical isomerization, 165
photophysical and
thermodynamic data, 160t
picosecond and nanosecond
difference TR-IR spectra, 166f
rhenium molecular
rectangle, 162f
ligand
alkylation, 166– 167
intramolecular sensitization, 167
stilbene-type, 167
multinuclear
linear-shaped multinuclear
complexes, 161– 163
molecular polygons, 160– 161
polymer C, 160
properties, 160
thermal activation, 161
photochemical CO elimination
electron-donating mechanisms,
147
low-spin d6 electron
configuration, 146
photoexcitation process, 147
photochemical ligand substitution
reaction, fac-[Re(diimine)
(CO)3PR3]þ
Arrhenius plots, 156f(^13) C NMR spectra, 152f
dissociative and associative
mechanisms, 151
energyvs.Re–CO distance, 158
IR absorption bands, 151
isomerization, 151
isosbestic points, 150– 151
modification effects, 152– 154
photophysical properties, 155t
P(OEt) 3 ligand, 150– 151
potential energies, 158
relaxation processes, 154– 155
stabilization and destabilization,
154
trans-effects, ligands, 160
transient IR absorption (TR-IR)
spectra, 151– 152
UV/Vis absorption spectral
changes, 150f
Re(I) diimine tetracarbonyl
complexes
irradiation, 149
reaction quantum yields, 149
Re–Re, Re–M, and Re–C bond
homolysis reactions
irradiation, 148
photoirradiation, 147– 148
Ru(bpy) 32 þ photosensititzer,
250 – 251, 251f
438 INDEX