Nanopatterns – Understanding Emergence of Properties at Scale

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Nanopatterns Understanding Emergence of
Properties at Scale

• Robert D. Cormia / Jill N. Johnsen
• Foothill College

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Overview

• Nanoscience gt the big ideas
• Emergence gt the missing idea
• Nanopatterns gt a new rubric
• Examples gt nanopatterns in use
• Future directions and practice

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Nanoscience Big Ideas

• 2006 workshops
• NCLT and SRI
• University of Michigan and Northwestern
  University
• Eight big ideas
• A textbook guide

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The Big Ideas

• Size and scale
• Matter
• Dominant Forces
• Properties are size dependent

• Models
• Tools
• Technology and society
• Self assembly

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The Missing Idea

• Emergence of properties at scale
• We talk about it all the time
• But no one ever explains it
• Because

Emergence is a very difficult topic to talk about
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Emergence Model
Properties
System behaviors
System Properties
Emergent Properties
Class properties
Archetype Behaviors
Process evolution
System
System Archetype
System process
System Constituents
Actor Interactions
Archetype process
Archetype
Process
Primitive interactions
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Nanopatterns

• Network archetypes
• Memorizing patterns, vs. structures
• Patterns of atoms in structural networks
• Atoms as nodes, each with atomic orbitals gt
  focus on bonding networks
• Network archetypes gt nanosystems
• Smaller motifs, that expand into systems

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Nanopatterns Rubric

• Networks of atoms
• Systems of physics
• Emergence of properties at scale

• Draw network of atoms for a structural system
• Sketch out chemical bonding network
• Look at the extended structure as a system

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Size Dependent Properties
Molecular Dynamics (MD) simulations of heat
transfer based on classical statistical mechanics
allow the atom to have thermal heat capacity
through kT energy. Here k is Boltzmanns constant
and T absolute temperature. The above picture
shows melting temperatures applied on the left
with the right maintained at freezing. The
simulation is discreted and submicron. But
lacking periodicity, MD solutions of discrete
nanostructures are invalid by QM. Here QM stands
for quantum mechanics. Unlike statistical
mechanics, QM forbids atoms in discrete submicron
nanostructures to have heat capacity, and
therefore the nanostructure cannot conserve EM
energy by an increase in temperature. Without
temperature changes, thermal conduction is
precluded at the nanoscale.
Melting point is an emergent property
Validity of Heat Transfer by Molecular Dynamics -
http//www.nanoqed.org/
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Phonon Network
http//en.wikipedia.org/wiki/Phonon
Images Wikipedia commons
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Size Dependent PropertiesNi nanoparticles gt
Nanomagnetism

• http//www.grin.com/en/doc/231229/size-dependent-m
  agnetic-properties-

http//www.flickr.com/photos/brookhavenlab/3191719
900/in/photostream
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Graphene as a System
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Graphene Nanostructure
Extended sp2 hybridized carbon and p-p network
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Nanostructures and Nanosystems from carbon
nano-motifs
nanostructure Nano-motif (or structural unit) Nanopattern Nanosystem

Graphene/graphite sp2 moiety bracket graphene hexagon Extended plane
Fullerene sp2 moiety cap hexagon/pentagon Enclosed sphere
Nanotube sp2 moiety mesh zigzag/armchair mesh Enclosed tube
Nanoonion sp2 moiety (ring?) zigzag/armchair swirl? Nanospheres?
Boron nitride nanomesh Trigonal BN BN hexagonal ring Planar honeycomb
Self Assembled Monolayers alkane (head and tail) 1-2 dimensional SAM 2 dimensional sheet
Liposomes phospholipid unit Phospholipid bilayer Spherical bilayers
Dendrimers g-0 functional branch Fractal branch (G-x) Spherical/functionalized macro-molecule
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Allotropes of carbon

• A - diamond
• B - graphite
• C - lonsdaleite
• D - C60 Buckminsterfullerene
• E - Amorphous carbon
• F - C70
• G - C540
• H - single-walled carbon nanotube 

http//en.wikipedia.org/wiki/Allotropes_of_carbon
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Nano-Onion
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(No Transcript)
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Borazine Nanomesh

• Borazine decomposition
• Forms ordered surface network
• One layer thick (like graphene)
• Extended structure
• Emergent properties

http//en.wikipedia.org/wiki/Nanomesh
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Borazine Nanomesh
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Networks of atoms in novel nanoscale structures

• Dancing Triangles' are formed by sulfur atoms on
  a layer of copper, which in turn rests upon a
  base, or 'substrate' of ruthenium. Scientists at
  Brookhaven Lab will study this type of
  configuration to understand how metal behaves on
  top of another. Layered metals are often used as
  catalysts, such as those that clean pollutants
  from automobile exhaust in catalytic converters.

Flickr Brookhaven Laboratory Stream
http//www.flickr.com/photos/brookhavenlab/3191719
710/in/photostream/
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Nanostructures

• Small networks of atoms
• Liposomes
• Dendrimers
• Carbon nanotubes
• Self Assembled Monolayers
• Unit cells of extended nanostructured materials
• Graphene
• Nanomesh

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Each phospholipid is a structural motif, a
structure in itself, and a building block in a
larger system
http//en.wikipedia.org/wiki/Phospholipid
A system of phospholipids that is an emergent
structure itself. Liposomes and cellular
vessicles
http//en.wikipedia.org/wiki/Exosome_(vesicle)
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Nanosystems
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Summary / References

• Nanopatterns rubric
• Networks of atoms
• Systems of physics
• Emergence of properties at scale
• Nanostructures to nanosystems
• The Big Ideas in Nanoscale Science and
  Engineering Stevens, S. Y., Sutherland, L.,
  Schank, P., Krajcik, J. (2007).
• http//www.mcrel.org/Nanoteach/pdfs/big_ideas.pdf