Sts g5 nanotechnology

• Nanotechnology


  Branch of science and engineering devoted to designing, producing, and using structures, devices, and systems by manipulating atoms and molecules at nanoscale
• Nanoscale


  Having one or more dimensions of the order of 100 nanometres (100 millionth of a millimetre) or less
• Prefix ‘nano’


  A Greek prefix meaning ‘dwarf’ or something very small, depicting one thousand millionth of a meter (10−9 m)
• Nanoscience


  The study of structures and molecules on the scales of nanometers ranging between 1 and 100 nm
• Modern nanotechnology truly began when the scanning tunneling microscope allowed scientists and engineers to see and manipulate individual atoms


  1981
• IBM scientists Gerd Binnig and Heinrich Rohrer won the 1986 Nobel Prize in Physics for inventing the scanning tunneling microscope
• The Binnig and Rohrer Nanotechnology Center in Zurich, Switzerland, continues to build on the work of these pioneering scientists
• Modern nanotechnology may be quite new, but nanometer-scale materials have been used for centuries
• As early as the 4th century, Roman artists discovered that adding gold and silver to glass created a startling effect
• The glass appeared slate green when lit from the outside, but glowed red when lit from within due to nanoparticles of gold and silver suspended in the glass solution
• The most famous surviving example of this technique is a ceremonial vessel, the Lycurgus Cup
• In 2006, modern microscopy revealed the technology of Damascus steel, a metal used in South Asia and the Middle East until the technique was lost in the 18th century
• Swords made with Damascus steel are legendary for their strength, durability, and ability to maintain a very sharp edge
• One of the most well-known examples of premodern use of nanomaterials is in European medieval stained-glass windows
• U.S. physicist Richard Feynman is considered the father of nanotechnology
• Feynman introduced the ideas and concepts behind nanotech in a 1959 talk titled "There’s Plenty of Room at the Bottom"
• Norio Taniguchi was the first to use and define the term “nanotechnology” in 1974
• Nano


  Processing of separation, consolidation, and deformation of materials by one atom or one molecule
• Scanning Probe Microscopy (SPM)


  A family of microscopy techniques that form images of surfaces using a physical probe that scans the specimen
• SPM

  • Allows for imaging, measuring, and manipulating matter at the nanoscale
  • Two common types are Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM)
• Atomic Force Microscopy (AFM)


  Uses a cantilever with a sharp tip that scans the sample surface
• Scanning Tunneling Microscopy (STM)


  Uses a conducting tip that is brought very close to the surface of a conducting sample
• Molecular modelling


  Encompasses all theoretical methods and computational techniques used to model or mimic the behavior of molecules
• Quantum Mechanics (QM) Methods

  • Hartree-Fock (HF)
  • Density Functional Theory (DFT)
  • Post-Hartree-Fock Methods
• Hartree-Fock (HF)


  An approximate method that simplifies the many-electron problem into a set of single-electron problems
• Density Functional Theory (DFT)


  Uses electron density rather than wavefunctions to describe electronic properties
• Post-Hartree-Fock Methods

  Include methods like Møller-Plesset perturbation theory (MP2) and Coupled Cluster (CC)
• Molecular Mechanics (MM) Methods

  • AMBER
  • CHARMM
  • OPLS
• AMBER


  Widely used for biomolecules
• CHARMM

  Commonly used for proteins, lipids, and nucleic acids
• OPLS

  Optimized for simulating organic and biomolecular systems
• These methods use classical mechanics to model molecular systems
• Atoms are treated as spheres and bonds as springs, with parameters derived from experimental data and QM calculations
• Molecular Dynamics (MD) Simulations


  Compute the time-dependent behavior of a molecular system by solving Newton's equations of motion
• Monte Carlo (MC) Simulations


  Use random sampling to explore the configuration space of a molecular system
• Nanomaterials


  • Materials with at least one external dimension that measures 100 nanometres or less
  • May be in the form of particles, tubes, rods or fibres
• Nanoparticles


  Sub-nanosized colloidal structures composed of synthetic or semi-synthetic polymers
• Nanoparticles are an important component of atmospheric pollution and key ingredients in many industrialized products
• Nanoparticles


  • Composed of three layers: surface layer, shell layer, and core
• Physical properties of nanoparticles

  • Highly mobile in the free state
  • Enormous specific surface areas
  • May exhibit quantum effects