Theoretical analysis of a carbon-carbon dimer placement tool for diamond mechanosynthesis.

Density functional theory is used with Gaussian 98 to analyze a new family of proposed mechanosynthetic tools that could be employed for the placement of two carbon atoms--a carbon-carbon (CC) dimer--on a growing diamond surface at a specific site. The analysis focuses on specific group IV-substituted biadamantane tool tip structures and evaluates their stability and the strength of the bond they make with the CC dimer. These tools should be stable in a vacuum and should be able to hold and position a CC dimer in a manner suitable for positionally controlled diamond mechanosynthesis at room temperature.