Knowledge Bank

Recent studies have shown that proton transfer processes cease at low temperatures in $H2O(s)$ and $NH3(s)$. Consequently, it is possible, via a matrix isolation approach to isolate molecules such as $D2O$ and $ND3$, intact, in otherwise pure glassy or crystalline $H2O$ and $NH3$. $D2O$ has been studied isolated in amorphous and crystalline $H2O$ where decoupling of the vibrational modes has permitted evaluation of the relative importance of correlation field effects, the coupling of intramolecular bond oscillators and Fermi resonance $\mathrm{<mrow\; data-mjx-texclass="ORD">1,2,3,</mrow>}$ similar decoupling results are now available for $ND3$ in $NH3(s)$ showing that the correlation field effects are small and nearly of magnitude less than for crystalline or amorphous $H2O$. These results will be presented together with spectroscopically determined proton exchange rates and conclusions regarding energy barriers and mechanisms for proton exchange.