Ethynylbenzene analysis of the 2790 Å absorption system

Characterization of excited electronic and vibronic states of platinum metal compounds with chelate ligands by highly frequency-resolved and time-resolved spectra

“…3.1). Similar conclusions with respect to the spatial extension of electronic states and the occurrence of vibrational satellites in vibronic spectra have been drawn for a long time for many other larger molecules (in particular see [91,240,241] and references therein; cf. also [83,85,104,108] Line-Narrowed Excitation Spectra and [Ru(bpy)3] 2 § Aggregates.…”

“…Beside the shift of the electronic transition energy, the emission properties of [Pt(bpy-ds)2] 2+ exhibit further changes with respect to [Pt(bpy-hs)2] 2+. Similar effects are well known and are usually observed upon deuteration of emitting centers (e.g., see [37,44,60,74,85,[102][103][104][105][106][107]). In particular, (1) all vibrational energies are red-shifted.…”

“…Moreover, if specific positions or spatial regions of the compound are isotopically designated, one may even obtain information about the spatial spread of the wave functions involved in the emission process. Similar investigations have already been carried out for organic molecules [74,102,103] as well as for transition metal complexes [44,60,74,85,104]. Here, we focus on [Pt(bpy-ds)2] 2+ and [Pt(bpy-hs)(bpy-ds)] 2+.…”

Phenylacetylene: A Hydrogen Bonding Chameleon

“…As mentioned earlier, the Fermi resonance bands in phenylacetylene arise due to the coupling of the acetylenic CÀH stretching vibration with the combination band of one quantum of the CC stretching vibration and two quanta of the acetylenic CÀH out-of-plane bending mode. [52,53] The disappearance of Fermi resonance bands indicates that the water molecule is interacting with the acetylenic moiety of phenylacetylene. However, formation of the CÀH···O hydrogen-bonded complex can be ruled out due to the fact that the CÀH stretching vibration shifts only marginally by about 3 cm À1 from the corresponding unperturbed oscillator in bare phenylacetylene at 3334 cm À1 .…”

“…The two strong transitions have been assigned to arise from Fermi resonance coupling between the acetylenic CÀH stretching vibration with the combination mode of one quantum of the acetylenic CC stretching mode and two quanta of the acetylenic CÀH out-of-plane bending mode. [52,53] The weaker transitions present in the spectrum have been assigned to higher-order coupling terms. [53] The two-state depertubation analysis based on the two strong transitions observed in the FDIR spectrum places the unperturbed (zero-order) acetylenic CÀH stretching vibration at 3334 cm À1 with a coupling constant of 9 cm…”