Dalton communications. Synthesis, spectroscopy and electrochemistry of luminescent [Re V N{Ph2P(CH2)2PPh2}(MeCN)]2+

Excited-State Distortions Determined from Structured Luminescence of Nitridorhenium(V) Complexes

“…A single progression of broad peaks is observed in all spectra with an average spacing between 1075 and 1100 cm -1 and with an experimental uncertainty in choosing the peak maxima of ±100 cm -1 . These values are within the range of rhenium−nitrogen triple bonds reported in the literature. ,− …”

“…The series of compounds investigated all produce structured emission spectra upon excitation at low temperature. Nitridorhenium(V) compounds are known to luminesce, ,− and some have been observed to produce vibronic structure. ,, The structure has been assigned to the ReN vibration, ,, but the excited state has never been analyzed. Detailed assignments of the modes involved in the emitting state will allow for an estimate of the ReN bond length change in the excited state.…”

Synthesis and Photoluminescence of Tetracyanidonitridorhenium(V) Complexes with Five-Membered N-Heteroaromatic Ligands and Photoluminescence-Intensity Change

“…The complexes show the bands at 405–418 nm. The peak maximum wavelengths are similar to those observed for the six-coordinate tetracyanidonitridorhenium­(V) complexes, [ReN­(CN) 4 L] 2– (L = pyridine, MeOH, and acetone). , The band can be ascribed to the transition (d xy ) 2 → (d xy ) 1 (d π* ) 1 (d π* = d xz , d yz ) with p π (N 3– )–d π overlap. − This electronic transition between the highest energy occupied molecular orbital and lowest energy unoccupied molecular orbital is well characterized in d 2 nitridorhenium­(V) complexes. − The spectroscopic and photophysical data of the complexes in the crystalline phase are shown in Table . The emission spectra in the crystalline phase at 296 K are shown in Figures and .…”

“…1000 cm –1 , whose value corresponds to the ν ReN stretching band frequencies. The emission spectra are typical for the luminescence of a nitridorhenium­(V) complex. − From these results, we assigned the emissive excited state of 2 , 3 , 4 , and 6 to 3 [(d xy ) 1 (d xz or d yz ) 1 ] with the p π (N 3– )–d π overlap. The temperature ( T ) dependences of the emission spectrum and the τ em value of 2 in the crystalline phase were studied in the T range, 80 < T < 296 K as the data were shown in Figure S3 and Table S2 in the Supporting Information.…”

“…A nitridorhenium­(V) complex possesses a coordination site (axial site) at the trans position of the nitrido, and the site is influenced strongly by the trans effect of the nitrido. − Therefore, the site is labile, the sixth ligand is not necessary, and the five- and six-coordinate complexes are both stable . In addition, some types of the both five- and six-coordinate complexes show luminescence. − In the tetracyanidonitridorhenium­(V) complex, the emission quantum yield of the five-coordinate complex is low (Φ em < 0.01) and, thus, the complex is almost nonemissive by naked eyes . The six-coordinate complex shows intense luminescence in the solid state at 296 K. , Therefore, the luminescence on–off reaction using the weak coordination site is promising for the complex.…”