Some of the finer points of the mechanism still constitute an active areas of research. This process is referred to as the Grotthuss mechanism after its discoverer. In other words, only minor mass movement is required by simply shortening some bonds a bit, and slightly elongating others, a proton at the left side of a group of molecules (top row in the following figure) can "reappear" on the right side of the chain (bottom row) extremely rapidly. In solvents with hydrogen bonded clusters or chains (water would be one such example), this process can be repeated within the cluster thus allowing the proton to cover large distances (from one side of the cluster to the other) on a very short timescale. This energetically compensating process reduces the activation energy required for proton transfer. If you rely on programs that use a lot of memory and processing power, it’s best to evaluate your memory allowance and daily consumption and. Identify programs that slow down your computer. If hydrogen bonding is present, then the proton only needs to elongate one bond (the initial bond) while simultaneously shortening the hydrogen bond in order to effect transfer from one molecule to the next. There are two ways to fix this: first, decreasing the number of programs running, and second, increasing your computer’s memory and processing power. A nice, brief and not overly-mathematical introduction to tunneling can be found here.ĭashed line - thermally activated processĪ second reason why proton transfer is so facile relates to hydrogen bonding. Proton tunneling becomes particularly important at low temperatures where the available thermal energy may be inadequate for an activated process ( e.g. Due to their low mass, protons can tunnel through barriers, they don't always have to go over the barrier in an activated process.
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