Results 261 to 270 of about 24,331 (288)

Tuning the Homo–Lumo Gap in Π-Bridged Bis(Phosphaalkenes)

Phosphorus, Sulfur, and Silicon and the Related Elements, 2013
Abstract The HOMO–LUMO gap in a series of π-bridged bis(phosphaalkenes) is investigated by theoretical methods. The deshielding of the experimental 31P-NMR chemical shifts of a selection of these compounds does not correlate with a decrease of their calculated HOMO–LUMO gaps.
Andreas Orthaber, Rudolf Pietschnig
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Thermal routes to low HOMO–LUMO energy gap poly(arylenevinylene)s

Journal of Materials Chemistry, 2001
We have prepared poly(2,5-dimethoxy-1,4-phenylenevinylene) (DMEOPPV) and poly (2,5-thienylenevinylene) (PTV) via xanthate precursor polymer routes. The respective precursor polymers can be thermally converted to their corresponding conjugated polymers without the need for acid catalysis.
Mitchell, William J., Pena, Christophe, Burn, Paul L.   +2 more
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Tuning the HOMO–LUMO gap of SiC quantum dots by surface functionalization

Chemical Physics Letters, 2012
Abstract We present density-functional theoretical results of structural, electronic and optical properties of bare and surface passivated (–H, –OH, –NH 2 ) stoichiometric Si n C n ( n  = 10, 16, 28, 37, 43, 55, 68) quantum dots (QDs) as a function of the size of the dots.
Supriya Saha, Pranab Sarkar
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Tuning of the HOMO–LUMO Gap of Symmetrical and Unsymmetrical Ferrocenyl‐Substituted Diketopyrrolopyrroles

European Journal of Organic Chemistry, 2015
AbstractFerrocenyl‐substituted diketopyrrolopyrroles (DPPs) with the symmetrical π‐bridged donor–acceptor (D–π–A) frameworks D′–π–D–A–D–π–D′ and D′–A′–D–A–D–A′–D′ as well as unsymmetrical D–A–D–π–D′ and D–A–D–A′–D′ frameworks were designed and synthesized by a Pd‐catalyzed Sonogashira cross‐coupling reaction followed by a [2+2] cycloaddition ...
Yuvraj Patil, Thaksen Jadhav, Bhausaheb Dhokale, Rajneesh Misra   +3 more
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Amide-Linked Heterobi- and Heterotermetallocenes with Very Low HOMO–LUMO Gaps

Organometallics, 2011
The novel heterobi- and heterotermetallocenes [Fc-NHCO-Cc]+ (1) and [Fc-NHCO-Cc-CONH-Fc]+ (2) have been prepared by amide coupling of aminoferrocene and cobaltocenium carboxylic acid or 1,1′-cobaltocenium dicarboxylic acid. Very small differences of the redox potentials, ΔG0 ≈ 1 V, were observed due to the electron-donating and electron-withdrawing ...
Hannah Huesmann, Christoph Förster, Daniel Siebler, Teuta Gasi, Katja Heinze   +4 more
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The Near-Mid-IR HOMO–LUMO gap in amide linked porphyrin–rhodamine dyads

Chemical Communications, 2013
Novel amide linked porphyrin-rhodamine dyads yield utmost intense red-shifted electronic transitions beyond the near-infrared region.
José A B, Ferreira, Vanda V, Serra, Antonio, Sánchez-Coronilla, Sónia M G, Pires, Maria A F, Faustino, Artur M S, Silva, Maria G P M S, Neves, José A S, Cavaleiro, Sílvia M B, Costa   +8 more
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Substituent Effects in Pentacenes: Gaining Control over HOMO−LUMO Gaps and Photooxidative Resistances

Journal of the American Chemical Society, 2008
A combined experimental and computational study of a series of substituted pentacenes including halogenated, phenylated, silylethynylated and thiolated derivatives is presented. Experimental studies include the synthesis and characterization of six new and six known pentacene derivatives and a kinetic study of each derivative under identical ...
Irvinder, Kaur, Wenling, Jia, Ryan P, Kopreski, Selvapraba, Selvarasah, Mehmet R, Dokmeci, Chandrani, Pramanik, Nicol E, McGruer, Glen P, Miller   +7 more
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Gold-Caged Metal Clusters with Large HOMO−LUMO Gap and High Electron Affinity

Journal of the American Chemical Society, 2005
We report a series of isoelectronic gold-caged metal clusters, M@Au14 (M = Zr, Hf), and anion clusters, M@Au14- (M = Sc, Y), all having a calculated HOMO-LUMO gap larger than the well-known tetrahedral cluster Au20-the 3D metal cluster with a very large measured HOMO-LUMO gap (1.77 eV). The clusters M@Au14 (M = Sc, Y) also exhibit a calculated electron
Yi, Gao, Satya, Bulusu, Xiao Cheng, Zeng
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Explaining the Closure of Calculated HOMO-LUMO Gaps in Biomolecular Systems

2015
It is quite alarming that several publications exist in the literature raising serious questions about the applicability of DFT techniques to large-scale systems such as water clusters and proteins [1, 2, 3, 4, 5, 6].
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Novel oligothiophenes with reduced HOMO-LUMO band gap for Optoelectonics

2017
Here we present the synthesis of A-π-D-π-A thiophene-based oligomers (Figure 1); in the design of these materials we incorporated both electron-donor and electron-acceptor groups by having a central donor dithienosilole, two terminal methyldicyanovinyl acceptor groups and two bithienyl units, functionalised with alkyl or alkylsulfanyl chains, as π ...
Francesca Parenti, BUFFAGNI, MIRKO, Alfonso Zambon, Monica Caselli, Davide Vanossi, Adele Mucci   +5 more
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