Feb 18, 2016

Saved: Fabulous 2 BR, 1 Ba condo - few steps from Quatama MAX station (Beaverton) $1200 2bd 780ft2


Fabulous 2 BR, 1 Ba condo - few steps from Quatama MAX station (Beaverton) $1200 2bd 780ft2 by via craigslist portland | apts/housing for rent search "beaverton" http://ift.tt/1KUONv5

Feb 17, 2016

Saved: How To Make DIY Liquid Castile Soap


How To Make DIY Liquid Castile Soap by Erica via Northwest Edible Life http://ift.tt/1PFr1lS

Feb 13, 2016

Saved: 5063 SW 173rd Ave. (Beaverton) $1395 2bd 1400ft2


5063 SW 173rd Ave. (Beaverton) $1395 2bd 1400ft2 by via craigslist portland | apts/housing for rent search "beaverton" http://ift.tt/1Rx3VjG

Feb 1, 2016

Saved: Clean and quiet 2BR with fenced yard, pets ok (Beaverton) $1100 2bd


Clean and quiet 2BR with fenced yard, pets ok (Beaverton) $1100 2bd by via craigslist portland | apts/housing for rent search "hillsboro" http://ift.tt/1ZTzynR

Saved: 1482 SW 204th Avenue -- Open Floor Plan (Beaverton) $1495 3bd 1412ft2


1482 SW 204th Avenue -- Open Floor Plan (Beaverton) $1495 3bd 1412ft2 by via craigslist portland | apts/housing for rent search "hillsboro" http://ift.tt/1TeoMsn

Dec 21, 2015

Through-space transfer of chiral information mediated by a plasmonic nanomaterial


Through-space transfer of chiral information mediated by a plasmonic nanomaterial by Saeideh Ostovar pour via Nature Chemistry http://ift.tt/1JTukni http://ift.tt/1hvdawn

Oct 5, 2015

Singlet–Triplet Splittings in the Luminescent Excited States of Colloidal Cu+:CdSe, Cu+:InP, and CuInS2 Nanocrystals: Charge-Transfer Configurations and Self-Trapped Excitons

Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
J. Am. Chem. Soc., Article ASAP
DOI: 10.1021/jacs.5b08547
Publication Date (Web): September 21, 2015
Copyright © 2015 American Chemical Society

Abstract

Abstract Image
The electronic and magnetic properties of the luminescent excited states of colloidal Cu+:CdSe, Cu+:InP, and CuInS2 nanocrystals were investigated using variable-temperature photoluminescence (PL) and magnetic circularly polarized luminescence (MCPL) spectroscopies. The nanocrystal electronic structures were also investigated by absorption and magnetic circular dichroism (MCD) spectroscopies. By every spectroscopic measure, the luminescent excited states of all three materials are essentially indistinguishable. All three materials show very similar broad PL line widths and large Stokes shifts. All three materials also show similar temperature dependence of their PL lifetimes and MCPL polarization ratios. Analysis shows that this temperature dependence reflects Boltzmann population distributions between luminescent singlet and triplet excited states with average singlet–triplet splittings of ∼1 meV in each material. These similarities lead to the conclusion that the PL mechanism in CuInS2 NCs is fundamentally different from that of bulk CuInS2 and instead is the same as that in Cu+-doped NCs, which are known to luminesce via charge-transfer recombination of conduction-band electrons with copper-localized holes. The luminescence of CuInS2 nanocrystals is explained well by invoking exciton self-trapping, in which delocalized photogenerated holes contract in response to strong vibronic coupling at lattice copper sites to form a luminescent excited state that is essentially identical to that of the Cu+-doped semiconductor nanocrystals.
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Bidirectional Electron Transfer Capability in Phthalocyanine–Sc3N@Ih–C80 Complexes

Department of Organic Chemistry, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
IMDEA Nanociencia, Faraday 9, 28049 Madrid, Spain
§ Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
Department of Chemistry, Tokyo Gakugei University, Koganei, Tokyo 184-8501, Japan
Department of Chemistry, University of Texas at El Paso, El Paso, Texas 79968, United States
J. Am. Chem. Soc., Article ASAP
DOI: 10.1021/jacs.5b06454
Publication Date (Web): September 24, 2015
Copyright © 2015 American Chemical Society

Abstract

Abstract Image
To activate oxidative and/or reductive electron transfer reactions, N-pyridyl-substituted Sc3N@Ih–C80 (4) and C60 (3) fulleropyrrolidines have been prepared and axially coordinated to electron-rich (1) or electron-deficient (2) Zn(II)phthalocyanines (Zn(II)Pcs) through zinc-pyridyl, metal–ligand coordination affording a full-fledged family of electron donor–acceptor ensembles. An arsenal of photophysical assays as they were carried out with, for example, 1/4 and 2/4 show unambiguously that a Zn(II)Pc-to-Sc3N@Ih–C80 photoinduced electron transfer takes place in the former ensemble, whereas a Sc3N@Ih–C80-to-Zn(II)Pc electron transfer occurs in the latter ensemble. To the best of our knowledge, this is the first time that a fullerene-based molecular building block shows an electron transfer dichotomy, namely acting both as electron-acceptor or electron-donor, and its outcome is simply governed by the electronic nature of its counterpart. In light of the latter, the present work, which involves the use of Sc3N@Ih–C80, one of the most abundant and easy-to-purify endohedral metallofullerenes, is, on one hand, a paradigmatic change and, on the other hand, an important milestone en-route toward the construction of easy-to-prepare molecular materials featuring switchable electron transfer reactivity.

Sep 22, 2015

2nd coordination sphere controlled electron transfer of iron hangman complexes on electrodes probed by surface enhanced vibrational spectroscopy

Chem. Sci., 2015, Advance Article

DOI: 10.1039/C5SC02560E

Iron hangman complexes exhibit improved catalytic properties regarding O2 and H2O2 reduction, which are attributed to the presence of a proton donating group in defined vicinity of the catalytic metal centre. Surface enhanced resonance Raman (SERR) and IR (SEIRA) spectro-electrochemistry has been applied concomitantly for the first time to analyse such iron hangman porphyrin complexes attached to electrodes in aqueous solution. While the SERR spectra yield information about the redox state of the central iron, the SEIRA spectra show protonation and deprotonation events of the 2nd coordination sphere. To investigate the influence of a proton active hanging group on the heterogeneous electron transfer between the iron porphyrin and the electrode, two hangman complexes with either an acid or ester functional group were compared. Using time resolved SERR spectroscopy the electron transfer rates of both complexes were determined. Complexes with an acid group showed a slow electron transfer rate at neutral pH that increased significantly at pH 4, while complexes with an ester group exhibited a much faster, but pH independent rate. SEIRA measurements were able to determine directly for the first time a pKavalue of 3.4 of a carboxylic hanging group in the immobilized state that shifted to 5.2 in D2O buffer solution. The kinetic data showed an increase of the heterogeneous electron transfer rate with the protonation degree of the acid groups. From these results, we propose a PCET which is strongly modulated by the protonation state of the acid hanging group via hydrogen bond interactions.


Graphical abstract: 2nd coordination sphere controlled electron transfer of iron hangman complexes on electrodes probed by surface enhanced vibrational spectroscopy

On the Mechanisms of Hydrogen-Atom Transfer from Water to the Heteronuclear Oxide Cluster [Ga2Mg2O5].+: Remarkable Electronic Structure Effects

Angewandte Chemie International Edition
Volume 54Issue 40pages 11861–11864September 28, 2015
DOI: 10.1002/anie.201505336


Abstract

Mechanistic insight into the homolytic cleavage of the O[BOND]H bond of water by the heteronuclear oxide cluster [Ga2Mg2O5].+ has been derived from state-of-the-art gas-phase experiments in conjunction with quantum chemical calculations. Three pathways have been identified computationally. In addition to the conventional hydrogen-atom transfer (HAT) to the radical center of a bridging oxygen atom, two mechanistically distinct proton-coupled electron-transfer (PCET) processes have been identified. The energetically most favored path involves initial coordination of the incoming water ligand to a magnesium atom followed by an intramolecular proton transfer to the lone-pair of the bridging oxygen atom. This step, which is accomplished by an electronic reorganization, generates two structurally equivalent OH groups either of which can be liberated, in agreement with labeling experiments.