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191.
Fifth-order nonlinear visible-infrared spectroscopy is used to probe coherent and incoherent vibrational energy relaxation dynamics of highly excited vibrational modes indirectly populated via ultrafast photoinduced back-electron transfer in a trinuclear cyano-bridged mixed-valence complex. The flow of excess energy deposited into four C≡N stretching (ν(CN)) modes of the molecule is monitored by performing an IR pump-probe experiment as a function of the photochemical reaction (τ(vis)). Our results provide experimental evidence that the nuclear motions of the molecule are both coherently and incoherently coupled to the electronic charge transfer process. We observe that intramolecular vibrational relaxation dynamics among the highly excited ν(CN) modes change significantly en route to equilibrium. The experiment also measures a 7 cm(-1) shift in the frequency of a ~57 cm(-1) oscillation reflecting a modulation of the coupling between the probed high-frequency ν(CN) modes for τ(vis) < 500 fs. 相似文献
192.
193.
Graham Smith Raymond C. Bott Daniel E. Lynch 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1155-1156
The 1:1 adduct of 4‐aminobenzoic acid (PABA) with 4‐am‐inobenzonitrile (PABN), C7H7NO2·C7H6N2, consists of a primary centrosymmetric cyclic hydrogen‐bonded PABA dimer interaction [O?O 2.640 (3) Å] peripherally linked into chains by weaker hydrogen bonds via a head‐to‐tail PABN interaction [N?N 3.179 (4) and N?O 3.062 (4) Å], and is linked between the chains by amine‐N (PABN) to amine‐N (PABA) interactions [N?N 3.233 (5) Å]. No proton transfer occurs. 相似文献
194.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):e536-e536
The structure of the title compound, C30H24Cl12N12S6, (I), comprises six symmetry unique molecules that vary only slightly in their N—C—S—C torsion angle. All the molecules are planar to within less than 3.1°. 相似文献
195.
Sumod George Ashwini Nangia Vincent M. Lynch 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):777-778
In the crystal structure of the title compound, C13H12N2O, N—H(anti)?O hydrogen bonds produce the so‐called urea α‐network and the N—H(syn) donor forms an unconventional N—H?π hydrogen bond. 相似文献
196.
Ruud Peters Ingrid Elbers Anna Undas Eelco Sijtsma Sophie Briffa Pauline Carnell-Morris Agnieszka Siupa Tae-Hyun Yoon Loïc Burr David Schmid Jutta Tentschert Yves Hachenberger Harald Jungnickel Andreas Luch Florian Meier Jovana Kocic Jaeseok Kim Byong Chon Park Barry Hardy Colin Johnston Kerstin Jurkschat Jrg Radnik Vasile-Dan Hodoroaba Iseult Lynch Eugenia Valsami-Jones 《Molecules (Basel, Switzerland)》2022,27(15)
197.
198.
D. Speliotis P. Judge W. Lynch J. Burbage R. Keirsted 《Journal of magnetism and magnetic materials》1993,120(1-3):172-176
Oriented particulate Ba-ferrite (BF) media have been known to exhibit very narrow switching field distributions, due to a confluence of reasons based on the particle morphology and the direction of their magnetic anistropy. In this study we report on extremely narrow switching fields observed in longitudinally oriented BF rigid disk coatings, which are primarily the result of strong positive magnetostatic interactions between adjacent platelets in the oriented assemblies. In the transverse direction, the interactions are negative, and the switching fields are large. 相似文献
199.
Larry R. Krepski Laurie E. Lynch Steven M. Heilmann Jerald K. Rasmussen 《Tetrahedron letters》1985,26(8):981-984
Tetronic acids and β-keto-γ-butyrolactones are easily prepared by the zinc induced reaction of O-trimethylsilylated cyanohydrins and α-bromoesters. 相似文献
200.