Download or read book Investigation of Low dimensional Supramolecular Architectures by Low temperature Scanning Tunneling Microscopy written by Sylvain Clair and published by . This book was released on 2004 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scanning Tunneling Microscopy STM Studies of Low Dimensional Materials written by Ling Fu and published by . This book was released on 2017 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book STM Investigation of Molecular Architectures of Porphyrinoids on a Ag 111 Surface written by Florian Buchner and published by Springer Science & Business Media. This book was released on 2010-11-09 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: The functionalization of surfaces on the nanoscale is one of the most fascinating and at the same time challenging topics in science. It is the key to tailoring catalysts, sensors, or devices for solar energy conversion, whose functional principle is based on the interaction of an active solid surface with another (liquid or gaseous) phase. As an example, planar transition metal complexes adsorbed on solid supports are promising candidates for novel heterogeneous catalysts. An important feature of these catalysts, compared to supported metal clusters, is the fact that the active sites, i. e. , the coordinated metal centers with their vacant axial coordination sites, are well de?ned and uniform. Metalloporphyrinoids are particularly suitable in this respect because they combine a structure forming element—the rigid molecular frame, which often induces long range order—with an active site, the coordinated metal ion. Its planar coordination environment leaves two axial coordination sites available for additional ligands. If adsorbed on a surface, one of these axial sites is occupied by the underlying substrate. The resulting electronic interaction with the surface can be used to tailor the electronic structure and thereby the reactivity of the metal center. The remaining site is free for the attachment of molecules (sensor functionality) and/or operates as a reaction center (single-site catalysis). Prototype examples are omnipresent in nature, where in particular metallo-tetrapyrrols play a decisive role in important biological processes, with the most prominent examples being iron porphyrins in heme, magnesium porphyrins in chlorophyll, and cobalt corrin in vitamin B12.
Download or read book Low Temperature Scanning Tunneling Microscopy Studies of Surfaces and Molecules written by Lisa Marie Wesoloski and published by . This book was released on 2006 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology is described as an emerging science discipline that is expected to have a greater impact on life as we know it than any innovation since the industrial revolution. Superior, cheaper, stronger and more efficient products are predicted to change the way we live, use technology and conduct research. This dissertation focuses on a remarkable instrument, the low temperature scanning tunneling microscope (LT-STM), which is a powerful tool that has played a significant role in revolutionizing the fields of nanoscience and nanotechnology. The work in this dissertation is divided into three sections. First, the fundamental principles of nanoscience and the history of microscopy are introduced. The second part provides a thorough study of Bardeen's formula and its application in STM. The third part describes experimental investigations involving the physicochemical properties of matter at the nanoscale conducted by means of LT-STM. Studies begin with bare substrate surfaces and successively build in complexity as small molecules, solvents, nanoclusters and large organic molecules are examined on surfaces. Experiments show that carbon monoxide exhibits chemical contrast, while oxygen shows a lack thereof. Solvents are demonstrated to weaken surface bonds and induce surface atom mass transport and the tip is shown to assist the diffusion. Manganese nanoclusters are shown to generate a localized electronic state on graphite by either an electronic or magnetic perturbation. The aromatic molecule, decacyclene (DC) is shown to exhibit both bias-dependent and tip-dependent contrast reversal. In addition, intermolecular interactions are found to compete with the surface-to-molecule interactions as dimers are observed on the surface. Two geometric orientations of the dimers are proposed to explain dimer characteristics and their relation to substrate-dependent properties. Lastly, DC molecules are examined at coverages in excess of a monolayer and shown to form ordered domains of the boat-shape conformation. This dissertation emphasizes the local modifications of electronic structures upon physisorption and the interplay between surface-to-molecule and molecule-to-molecule interactions, which demonstrate the various complexities occurring at the nanoscale.
Download or read book Proceedings of the National Academy of Sciences of the United States of America written by National Academy of Sciences (U.S.). and published by . This book was released on 2007 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Local Probe Investigation of the Electronic Structure of Molecule Based and Transition Metal Based Low Dimensional Systems Using Cryogenic Scanning Tunneling Microscopy and Spectroscopy written by Aaron Joe Bradley and published by . This book was released on 2015 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of the many fascinating topics in condensed matter physics, this dissertation aims to cover three subtopics in some detail: 1) Functionalization of surfaces - using single molecules and/or atoms to change the behavior of a surface. 2) Low dimensional systems - 0D, 1D, or 2D materials whose behavior is often drastically different from the 3D world. 3) 3D to 2D crossover - studying what happens to materials as they are thinned down from a bulk 3D morphology to a single 2D layer. In addition to these areas of research, there will also be a focus on the modifications I made to the Toucan STM, and the rationale behind those changes. This portion, in combination with Niv Levy's dissertation, should serve as a user's manual for that microscope.
Download or read book Low Temperature Scanning Tunneling Microscopy Studies of the Surface and Impurity States in Narrow Gap Semiconductors written by Sergei Urazhdin and published by . This book was released on 2002 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a New Low Temperature Scanning Tunneling Microscope to Study Mass Selected Cluster Deposition written by Harald Jödicke and published by . This book was released on 1999 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low temperature Scanning Tunneling Microscopy Studies on Model Catalyysts written by Maria Kulawik and published by . This book was released on 2006 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Molecular Nanotechnology Research and Application 2012 Edition written by and published by ScholarlyEditions. This book was released on 2012-12-26 with total page 1624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Molecular Nanotechnology Research and Application / 2012 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Molecular Nanotechnology. The editors have built Advances in Molecular Nanotechnology Research and Application / 2012 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Molecular Nanotechnology in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Advances in Molecular Nanotechnology Research and Application / 2012 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Encyclopedia of Supramolecular Chemistry Two Volume Set Print written by Jerry L. Atwood and published by CRC Press. This book was released on 2013-10-09 with total page 1745 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-volume Encyclopedia of Supramolecular Chemistry offers authoritative, centralized information on a rapidly expanding interdisciplinary field. User-friendly and high-quality articles parse the latest supramolecular advancements and methods in the areas of chemistry, biochemistry, biology, environmental and materials science and engineering, physics, computer science, and applied mathematics. Designed for specialists and students alike, the set covers the fundamentals of supramolecular chemistry and sets the standard for relevant future research.
Download or read book Low Temperature Scanning Tunneling Microscope Development Investigations of Au 111 and Ultra slow Vortex Dynamics of NbSe2 written by Jonghee Lee and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Nanoscience and Technology written by and published by Academic Press. This book was released on 2010-10-29 with total page 2785 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the Introduction: Nanotechnology and its underpinning sciences are progressing with unprecedented rapidity. With technical advances in a variety of nanoscale fabrication and manipulation technologies, the whole topical area is maturing into a vibrant field that is generating new scientific research and a burgeoning range of commercial applications, with an annual market already at the trillion dollar threshold. The means of fabricating and controlling matter on the nanoscale afford striking and unprecedented opportunities to exploit a variety of exotic phenomena such as quantum, nanophotonic and nanoelectromechanical effects. Moreover, researchers are elucidating new perspectives on the electronic and optical properties of matter because of the way that nanoscale materials bridge the disparate theories describing molecules and bulk matter. Surface phenomena also gain a greatly increased significance; even the well-known link between chemical reactivity and surface-to-volume ratio becomes a major determinant of physical properties, when it operates over nanoscale dimensions. Against this background, this comprehensive work is designed to address the need for a dynamic, authoritative and readily accessible source of information, capturing the full breadth of the subject. Its six volumes, covering a broad spectrum of disciplines including material sciences, chemistry, physics and life sciences, have been written and edited by an outstanding team of international experts. Addressing an extensive, cross-disciplinary audience, each chapter aims to cover key developments in a scholarly, readable and critical style, providing an indispensible first point of entry to the literature for scientists and technologists from interdisciplinary fields. The work focuses on the major classes of nanomaterials in terms of their synthesis, structure and applications, reviewing nanomaterials and their respective technologies in well-structured and comprehensive articles with extensive cross-references. It has been a constant surprise and delight to have found, amongst the rapidly escalating number who work in nanoscience and technology, so many highly esteemed authors willing to contribute. Sharing our anticipation of a major addition to the literature, they have also captured the excitement of the field itself in each carefully crafted chapter. Along with our painstaking and meticulous volume editors, full credit for the success of this enterprise must go to these individuals, together with our thanks for (largely) adhering to the given deadlines. Lastly, we record our sincere thanks and appreciation for the skills and professionalism of the numerous Elsevier staff who have been involved in this project, notably Fiona Geraghty, Megan Palmer and Greg Harris, and especially Donna De Weerd-Wilson who has steered it through from its inception. We have greatly enjoyed working with them all, as we have with each other.
Download or read book Scanning Tunneling Microscopy on Low Dimensional Systems written by Christian David Salazar Enríquez and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scanning Tunneling Microscopy of Two dimensional Materials written by Grady A. Gambrel and published by . This book was released on 2017 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-dimensional materials are of fundamental and practical interest due to the unique properties they exhibit. As they are only one layer or one atom thick, their physical and electronic properties are sensitive to their local environment, and may be manipulated by engineering variations within the materials. Incorporating these materials into electronic devices requires that their interactions are well understood so that they behave as predicted. For this reason, the study of defects, likely contaminants, and engineered structures is worthwhile. The scanning tunneling microscope is of particular use in such experiments as it can be used to characterize the atomic structure and locally measure the electronic properties of samples. Graphene islands were grown on Cu(111) in ultrahigh vacuum to study graphene/copper interactions with minimal surface adsorbates. Using in situ low-temperature scanning tunneling microscopy (STM), both the physical and electronic structure were measured with atomic spatial resolution and compared with those of clean copper regions. These measurements indicate a decrease in the work function relative to clean Cu(111) and reduced coupling of surface electronic states to the bulk. Other measurements find that both the band edge and effective mass of Shockley surface state electrons are infuenced by the graphene layer. Similarly, single-layer germanene was grown on and measured on Cu(111). A competing alloy process which forms Cu2Ge restricts notable germanene coverage to a substrate temperature range between 40 degrees and 150 degrees Celsius. Atomic resolution imaging and tunneling spectroscopy are used to distinguish germanene and Cu2Ge regions, and probe the interaction of both with the Cu(111) substrate. Germanene was found to be weakly coupled to the Cu(111), maintaining an incommensurate 3.8 Angstrom lattice but lack any clear signatures of the Dirac point. In contrast, a 4.4 Angstrom lattice is observed on Cu2Ge that is commensurate with a v3 x v3 R30 reconstruction of Cu(111), and distinct unoccupied electronic states are observed well above the sample Fermi level.
Download or read book Study of Two Dimensional Materials by Scanning Probe Microscopy written by Ryan Plumadore and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis explores structural and electronic properties of layered materials at the nanometre scale. Room temperature and low temperature ultrahigh vacuum scanning probe microscopy (scanning tunneling microscopy, scanning tunneling spectroscopy, atomic force microscopy) is used as the primary characterization method. The main findings in this thesis are: (a) observations of the atomic lattice and imaging local lattice defects of semiconducting ReS2 by scanning tunneling microscopy, (b) measurement of the electronic band gap of ReS2 by scanning tunneling spectroscopy, and (c) scanning tunneling microscopy study of 1T-TaS2 lattice and chemically functionalizing its defects with magnetic molecules.
Download or read book Trends in Nanophysics written by Alexandru Aldea and published by Springer Science & Business Media. This book was released on 2010-08-05 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores a variety of diverse issues in nanotechnology, including radiation-induced polymerization, cross-linking and grafting; Mossbauer study of nanomaterials; biomedical applications of nanomaterials; graphene and carbon nanotubes; and many more.
