Nanosecond laser flash photolysis and time resolved luminescence were used to study the photophysical processes for Eu((i-Bu)2PS2)3Phen (1) and Eu(C4H8NCS2)3Phen (2) complexes in acetonitrile. These complexes show a very weak red Eu3+ luminescence in spite of the fact that the phenanthroline molecule in triplet state is a good antenna to excite the red luminescence of many Eu(III)-Phen complexes. To determine the reasons of this effect the photoprocesses in solutions, containing the (i-Bu)2PS2− or C4H8NCS2− ions and free phenanthroline molecule, have been studied with the use of laser flash photolysis (266nm). It was shown that the phenanthroline in triplet excited state (TPhen*) deprives the electron from these dithiolate ions with a high rate constants close to 109M−1s−1. The transient spectra of phenanthroline anion-radical and dithiolate radicals were recorded which are in a good agreement with literature data. Since the effective concentration of dithiolate ions (L−) in the coordination sphere of 1 and 2 complexes is close to 10M the time of electron transfer between L− and TPhen* is in the range of 100ps or less. As the laser flash photolysis of solutions of 1 and 2 complexes with a 10ns time resolution failed to detect the spectra of phenanthroline anion-radical and dithiolate radicals, it indicates that the time of back electron transfer is less than 10−8s. Thus, the very weak red luminescence of 1 and 2 complexes is due to the electron transfer between ligands in the coordination sphere which successfully suppresses the energy transfer from the phenanthroline triplet state to Eu3+ ion.
Journal of Luminescence – Elsevier
Published: Aug 1, 2016
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera