Introduction It is an interesting question as to, starting with a few atoms, how the bulk materials reach their structure and related properties. Do they undergo any structural changes or even their smallest unit cell is similar to that in bulk material?
This question has been addressed by many. There are reasons to believe that the small clusters or nanoparticles are not just the fragments of bulk materials. There can be entirely different structures as well as bonds and bond strengths in clusters which can even differ from nanomaterials. It has been well established now that all the materials, may be metals, semiconductors or insulator clusters or nanomaterials, have size dependent physicochemical properties.
In most of the cases a cluster size is below 1 nm and that of nanoparticles is in the 1–100 nm range. Interestingly at such a small size even the shape of the material and interactions between clusters or nanomaterials decide the properties of the material. This opens up a huge possibility of tailor making the materials, which have different properties just due to their size, shape and/or assembly.
In this chapter we will discuss to some extent clusters, semiconductor metal nanomaterials and magnetic nanomaterials. Nanomaterials would mean 0-D, 1-D or 2-D materials with the relevant dimensions smaller than 100 nm to qualify them as nanomaterials.
The general analysis methods for all the nanomaterials are as mentioned.
In this chapter some additional relevant analysis is discussed for semiconductor and metal nanoparticles. The chapter closes with some additional properties like mechanical, structural, electrical and thermal properties of the nanomaterials in general.
