Abstract: The present invention provides a process for partially covering solid crystalline surfaces with lines of selected atoms or molecules, a procedure known as the atomic or molecular ‘patterning’ of such surfaces. The method utilizes a mechanism of Dipole-Induced Assembly (DIA) for the growth of lines of physisorbed dipolar molecules on crystalline surfaces is disclosed. In an exemplary embodiment, physisorbed 1,5 dichloropentane (DCP) on Si(100)?2×1 at room temperature is shown by scanning tunneling microscopy (STM) to self-assemble into molecular lines that grow predominantly perpendicular to the Si-dimer rows. Extensive simulations indicate that the trigger for formation of these lines is the displacement of surface charge by the dipolar adsorbate, giving rise to an induced uni-directional surface-field and hence surface buckling.

Abstract: A method for mask-free molecular or atomic patterning of surfaces of reactive solids is disclosed. Molecules adsorb at surfaces in patterns, governed by the structure of the surface, the chemical nature of the adsorbate, and the adsorbate coverage at the surface. The surface is patterned and then imprinted with the pattern by inducing localized chemical reaction between adsorbate molecules and the surface of the solid, resulting in an imprint being formed in the vicinity of the adsorbate molecules. When the imprinted molecular patterns are conjugated chains containing ? bonds along which electrical charge can flow the molecular patterns constitute molecular wires or the imprinted molecules constitute a molecular-scale device. The surface of the substrate can be doped by including n- or p-type dopants in the adsorbate molecules. These molecular wires are anchored to the substrate by using conjugated chains which can be chemically bound at intervals along the chains to the substrates.

Abstract: A method for mask-free molecular or atomic patterning of surfaces of reactive solids is disclosed. Molecules adsorb at surfaces in patterns, governed by the structure of the surface, the chemical nature of the adsorbate, and the adsorbate coverage at the surface. The surface is patterned and then imprinted with the pattern by inducing localized chemical reaction between adsorbate molecules and the surface of the solid, resulting in an imprint being formed in the vicinity of the adsorbate molecules. When the imprinted molecular patterns are conjugated chains containing &pgr; bonds along which electrical charge can flow the molecular patterns constitute molecular wires or the imprinted molecules constitute a molecular-scale device. The surface of the substrate can be doped by including n- or p-type dopants in the adsorbate molecules. These molecular wires are anchored to the substrate by using conjugated chains which can be chemically bound at intervals along the chains to the substrates.

Abstract: A method for mask-free molecular or atomic patterning of surfaces of reactive solids is disclosed. A molecular-scale pattern of adsorbate molecules is used in place of the conventional macroscopic “mask”. Molecules adsorb at surfaces in patterns, governed by the structure of the surface, the chemical nature of the adsorbate, and the adsorbate coverage at the surface. The surface is patterned and then marked or imprinted with the pattern by inducing localised chemical reaction between adsorbate molecules and the surface of the solid, resulting in an imprint being formed in the vicinity of the adsorbate molecules. In one aspect of the invention, photoinduced or electron-induced reaction of the patterned adsorbate leads to patterned reaction with the surface.

Abstract: A method for mask-free molecular or atomic patterning of surfaces of reactive solids is disclosed. A molecular-scale pattern of adsorbate molecules is used in place of the conventional macroscopic "mask". Molecules adsorb at surfaces in patterns, governed by the structure of the surface, the chemical nature of the adsorbate, and the adsorbate coverage at the surface. The surface is patterned and then marked or imprinted with the pattern by inducing localized chemical reaction between adsorbate molecules and the surface of the solid, resulting in an imprint being formed in the vicinity of the adsorbate molecules. In one aspect of the invention, photoinduced reaction of the patterned adsorbate leads to patterned photoreaction with the surface.

Abstract: Gases or gas mixtures are analyzed by a device and process involving laser-induced vibrational excitation of the gases or mixtures, followed by mass spectrometry. A sample of the gas is subjected to radiation, preferably infrared radiation, from a tunable laser, so as to casue vibrational-excitation of the sample by absorption of the radiation. The sample so treated is then subjected to mass spectrometry, which detects changes in the vibrational-excitation of the sample. Detection of such changes indicates infrared absorption by the sample at the wavelength at which the tunable laser is set. The wavelength of infrared absorption so determined is a characterizing property of the sample.