Molecular sized switch

Figure 5.1 Three compounds that were synthesized for studies in computing using electrostatic potentials. 1 is a molecular three-terminal junction that could be used as a molecular interconnect. 2 is a molecular-sized switch for which there is a corresponding equivalent of a source, drain and gate terminals of a bulk solid state FET. 3 is a can be an active OR or a passive NOR gate if positive logic is used or an AND or NAND gate if negative logic is used. ...

Metal nanotube membranes with electrochemically suitable ion-transport selectivity, which can be reversibly switched between cation-permeable and anion-permselective states, have been reported. These membranes can be viewed as universal ion-exchange membranes. Gold nanotube molecular filtration membranes have been made for the separation of small molecules (< 400 Da) on the basis of molecular size, eg. separation of pyridine from quinine (Jirage and Martin, 1999). 

Synthetic Molecular Machines and Polymer/ Monomer Size Switches that Operate Through Dynamic and Non-Dynamic Covalent Changes... 

Abstract The present chapter is focused on how synthetic molecular machines (e.g. shuttles, switches and molecular motors) and size switches (conversions between polymers and their units, i.e., conversions between relatively large and small molecules) can function through covalent changes. Amongst the interesting examples of devices herein presented are molecular motors and size switches based on dynamic covalent chemistry which is an area of constitutional dynamic chemistry. 

Keywords Constitutional changes Covalent changes Dynamic covalent chemistry Molecular machines Molecular motors Molecular switches Polymer/monomer switches Reversible polymers Size switches... 

Polymer/Monomer Size Switches Switching Between Small and Large Molecular Sizes... 

Synthetic Molecular Machines and Polymer/Monomer Size Switches... 

Fig. 13 The reversible conversion (here, mediated by metal ions M) of a copolymer (A-B) into a much smaller molecule (here, a macrocycle ABM) can be seen as a size-switch which consists of a dramatic change of molecular size (molecular diameter) modulated through external stimuli, and operates through dynamic covalent chemistry. See also Fig. 15...

We have seen how column switching can expedite separation of substances of interest, using techniques that take advantage of the differences in hydrophobicity, Coulombic force, molecular size, or steric hindrance of the analytes affinity and enzymatic reactions and the application of mass spectrophotometric analysis. 

A three-terminal system with one barrier could be reminiscent of a molecular-sized field effect transistor (FET) or switch in which there is a... 

Fig.16 Result of a computer simulation of the BRM Relative mobility Ii/Pq as a function of the molecular size i=N/50 for various switching times and 0=1.0. The mobility is constant at...

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