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In its continuing quest for smaller length scales, the electronics industry plans to introduce 157 nm as the next lithographic wavelength. Accordingly, there is a pressing need to develop photoresists that are more transparent, and pellicles that are both more transparent and more durable. With the advent and popularization of time-dependent density functional theory (TD-DFT), we now have a practical quantum chemical method for calculating excitation energies and transition moments in the vacuum ultraviolet (VUV) which can greatly assist in the scouting of highly transparent materials. We have performed TD-DFT calculations for a broad variety of fluorinated molecules and we will report calculated VUV photoabsorption spectra for a large family of model fluorohexanes. These calculations, which span a range from 1-fluorohexane to CH 3 CF 2 CF 2 CF 2 CF 2 CH 3 , illustrate some of the principles one may use to design low absorption polymeric materials.

The origin of two minor but enigmatic side bands in the Fourier-transform infrared spectrum (FTIR) of acetone oxime vinyl ether is resolved with density functional theory calculations. A comparison of vibrational frequencies as computed with Hartree–Fock self-consistent-field theory and density functional theory is carried out for acetone oxime vinyl ether, and N-(3-nitrobenzylidene)-p-phenylenediamine. Implications for molecular electronics are discussed.

The reaction of carbon monoxide with the stable carbene, 1,3-di-1-adamantylimidazol-2-ylidene, is reinvestigated experimentally. With the aid of high level ab initio density functional theory calculations the predicted stability of the putative ketene product is determined. No evidence is found for the existence of a stable ketene product.

The mechanism for the reaction of a hydrogen atom with a silicon surface trihydride species was investigated by ab initio molecular orbital techniques. This reaction is believed to be the final step in the overall mechanism for the etching of silicon surfaces by hydrogen atoms. The gas-phase reaction of disilane with a hydrogen atom to form silyl radical and silane was used as the model for the etching process.

Unexpected side reactions at the Pd center have been identified for Pd-catalyzed cyanation of haloarenes. In the presence of excess cyanide, these reactions can proceed with ease, interfering with every key step of the catalytic cycle and thereby disrupting the process. Mixed PPh3/CN- Pd(0) species easily activate the C−N bond of Bu4N+ to produce cleanly and selectively a novel hydride [(CN)3PdH]2- which is stable in the presence of extra CN- but easily undergoes HCN reductive elimination under CN--free conditions. While slow addition of 1 equiv of CN- to [(Ph3P)2Pd(Ph)I] leads to PhCN formation, quick mixing of the same complex with a 4-fold excess of CN- does not produce PhCN but rather leads to [(CN)3Pd(Ph)]2-. Reductive elimination of PhCN from the latter is strongly inhibited by small quantities of free cyanide.

The development of new organic semiconductors with improved electrical performance and enhanced environmental stability is the focus of considerable research activity. This paper presents the design, synthesis, optical and electrochemical characterization, crystal packing, modeling and thin film morphology, and organic thin film field effect transistor (OTFT) device data analysis for a novel 2,6-bis[2-(4-pentylphenyl)vinyl]anthracene (DPPVAnt) organic semiconductor. We observed a hole mobility of up to 1.28 cm2/V.s and on/off current ratios greater than 107 for OTFTs fabricated using DPPVAnt as an active semiconductor layer. The mobility value is comparable to that of the current best p-type semiconductor pentacene-based device performance. In addition, we found a very interesting relationship between the charge mobility and molecule crystal packing in addition to the thin film orientation and morphology of the semiconductor as determined from single-crystal molecule packing study, thin film X-ray diffraction, and AFM measurements. The high performance of the semiconductor ranks among the best performing p-type organic semiconductors reported so far and will be a very good candidate for applications in organic electronic devices.