Cubane
Cubane belongs to a typical class of molecular solids such as carbon clusters C60, C70 . Due to its peculiar structure i.e., the C-C-C bond angle is 90o rather than the customary 109.5o , cubane stores a great deal of energy, which implies its explosiveness. Cubane was firstly synthesized in 1964 13 but its remarkable properties, such as potential pharmaceutical applications, have been realized only recently. One of its derivatives, tetranitrocubane, is a very powerful explosive, yet it is...
Solubilities of Diamondoids in Supercritical Solvents
As mentioned before, adamantane and diamantane are the first two members in the diamondoid series, and the most prevalent diamondoid compounds in natural gas. Their measured solubilities in methane, ethane, and carbon dioxide, which are three major components of natural gas, have been reported here 15 . The experimental solubilities of adamantane C1oH16 in ethane, carbon dioxide, and methane at 333 K are presented in Table 1.6, whereas solubility data for diamantane C14H20 in ethane and carbon...
Structural and Electronic Properties 1121 Borane Clusters
Borane clusters have been classified according to the topology of their molecular frameworks. Accordingly, closo boranes from the Greek clovos, meaning cage are closed polyhedra, nido from the Latin nidus, meaning nest boranes are semi-closed polyhedra, and arachno from the Greek arachne, meaning spider's web boranes possess open structures 6 . Both nido and arachno boranes are neutral specie whereas closo boranes are stable as dianions of chemical formula Bn Hn 2-, with n 5-12. Figure 11.1...
Silicon and Germanium on Silicon Nitride
On the crystalline SiNx film grown on Si 111 shown in Figure 6.2b, Si and Ge atoms also nucleate into 3-D islands. However, the nucleation takes place almost uniformly all over the surface, and the nucleation density does not change sensitively with substrate temperature. This is mainly due to the existence of many surface defects that act as nucleation sites. Figure 6.12a is an image of Si clusters Figure 6.12. STM images of Si and Ge grown on crystalline SiNx Si 111 . a 5-nm Si deposited at...
Diamondoid Molecules
Diamondoid molecules are cagelike saturated hydrocarbons. These molecules are ringed compounds, that have a diamondlike structure consisting of a number of six-member carbon rings fused together. They are called diamondoid because they can be assumed as repeating units of the diamond. The most famous member of this group, adamantane, is a tricyclic saturated hydrocarbon tricyclo 3.3.1.1 decane . Figure 3.2. Molecular structures of adamantane, diamantane, and trimantane, the smaller diamondoids,...