Many supramolecular systems require their components to have suitable spacing and conformations relative to each other, and therefore easily-employed structural units are required.
Commonly used spacers and connecting groups include polyether chains, biphenyls and triphenyls, and simple alkyl chains. The chemistry for creating and connecting these units is very well understood.
nanoparticles, nanorods, fullerenes and dendrimers offer nanometer-sized structure and encapsulation units.
Surfaces can be used as scaffolds for the construction of complex systems and also for interfacing electrochemical systems with electrodes. Regular surfaces can be used for the construction of self-assembled monolayers and multilayers.
A nanoparticle
which historically has included nanopowder, nanocluster, and nanocrystal is a small particle with at least one dimension less than 100 nm. This definition can be fleshed out further in order to remove ambiguity from future nano nomenclature. A nanoparticle is an amorphous or semicrystalline zero dimensional nano structure with at least one dimension between 10 and 100nm and a relatively large size dispersion.
A nanocluster is an amorphous/semicrystalline nanostructure with at least one dimension being between 1-10nm and a narrow size distribution.
This distinction is an extension of the term "cluster" which is used in inorganic/organometallic chemistry to indicate small molecular cages of fixed sizes. A nanopowder is an agglomeration of noncrystalline nanostructural subunits with at least one dimention less than 100nm.
A nanocrystal is any nanomaterial with at least one dimension ≤ 100nm and that is singlecrystalline.
Any particle which exhibits regions of crystallinity should be termed nanoparticle or nanocluster based on dimensions. Nanoparticle research is currently an area of intense scientific research, due to a wide variety of potential applications in biomedical, optical, and electronic fields. The National Nanotechnology Initiative of the United States government has driven huge amounts of state funding exclusively for nanoparticle research.
Surface science
is the study of physical and chemical phenomena that occur at the interface of two phases, including solid-liquid interfaces, solid-gas interfaces, solid-vacuum interfaces, and liquid-gas interfaces. It includes the fields of surface chemistry and surface physics.
Some related practical applications are classed as surface engineering. The science encompasses concepts such as heterogeneous catalysis, semiconductor device fabrication, fuel cells, self-assembled monolayers and adhesives. Surface science is closely related with Interface and Colloid Science.
Interfacial chemistry and physics are common subjects for both. Methods are different. In addition, Interface and Colloid Science studies macroscopic phenomena that occur in heterogeneous systems due to peculiarities of interfaces.