Editing Nanotechnology (section)

===Larger to smaller: a materials perspective===
[[File:Atomic resolution Au100.JPG|right|thumb|Image of [[Surface reconstruction|reconstruction]] on a clean [[Gold]]([[Miller index|100]]) surface, as visualized using [[scanning tunneling microscopy]]. The positions of the individual atoms composing the surface are visible.]]

{{main|Nanomaterials}}

Several phenomena become pronounced as system size. These include [[statistical mechanics|statistical mechanical]] effects, as well as [[Quantum mechanics|quantum mechanical]] effects, for example, the "[[quantum]] size effect" in which the electronic properties of solids alter along with reductions in particle size. Such effects do not apply at macro or micro dimensions. However, quantum effects can become significant when nanometer scales. Additionally, physical (mechanical, electrical, optical, etc.) properties change versus macroscopic systems. One example is the increase in surface area to volume ratio altering mechanical, thermal, and catalytic properties of materials. [[Diffusion]] and reactions can be different as well. Systems with fast ion transport are referred to as nanoionics. The mechanical properties of nanosystems are of interest in research.