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The adsorption of pyrrole, aniline, 3-pyrroline, and pyrrolidine on the Si(001)-(2 × 1) surface has been studied using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Both pyrrole and aniline retain their aromatic character after bonding to the surface. Spectroscopic evidence indicates that each of these aromatic molecules can attach to the Si(001) surface via cleavage of one N-H bond, linking the molecule to the surface through a Si-N tether. Isotopic studies of pyrrole show evidence for additional cleavage of C-H bonds. While strong selectivity favoring bonding through the nitrogen atom is observed for the aromatic molecules, the unsaturated molecule 3-pyrroline shows evidence for at least two bonding configurations. XPS and FTIR data show that 3-pyrroline can bond either through the nitrogen atom with cleavage of an N-H bond, or through the CdC bond via the surface equivalent of a [2 + 2] cycloaddition reaction. Pyrrolidine appears to bond only through the nitrogen atom. Potential factors controlling the selectivity in bonding and the role of aromaticity in controlling reaction pathways on silicon surfaces are discussed. † Part of the special issue "John T. Yates, Jr. Festschrift".

Superhydrophobic surfaces on engineering materials are prepared via a convenient solution‐immersion method. The binary geometric structures at the micro‐ and nanometer scale bestow superhydrophobic properties on the surfaces. The surfaces show stable superhydrophobicity even in many corrosive solutions, such as acidic or basic solutions over a wide pH range, and also in salt solutions. The procedure is time‐saving, inexpensive, and fairly facile to carry out. It is expected that this facile technique will accelerate the large‐scale production of superhydrophobic engineering materials with new industrial applications.

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The interactions of primary, secondary, and tertiary alkylamines with the Si(001) surface have been investigated using x-ray/ultraviolet photoelectron spectroscopy, Fourier transform infrared spectroscopy and scanning tunneling microscopy. Experimental and computational results show that alkylamines bond to the surface through the nitrogen atom. Primary alkylamines such as hexylamine bond to the surface by breaking only one N–H bond. Secondary alkylamines such as dimethylamine and N-methylpentylamine cleave only the N–H bond, leaving the N–C bonds intact. Tertiary alkylamines, such as trimethylamine and N,N-dimethylbutylamine, can form stable dative-bonded adducts on the surface that are characterized by very high N(1s) binding energies of 402.2 eV. The ability to form dative-bonded adducts between tertiary alkylamines and Si(001) stems from the capability of electron transfer from nitrogen to the surface. Our results show that this charge exchange controls the propensity for N–H vs N–C bond cleavage.