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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig1.eps} \end{figure}$ Figure 1: Optimized structures of transition states for the synchronous hydrogen-exchange reaction in methanol (H-H exchange TS) and in protonated methanol (H-H exchange TSH⁺) obtained with the B3LYP method. Bond distances are in Å and bond angles are in degrees. The relative transition state energies with the CCSD(T) method are +148.6 kcal mol^-1 for TS and +148.9 kcal mol^-1 for TSH⁺.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig2.eps} \end{figure}$ Figure 2: The upper panels show the optimized structures of methanol, its hydrogen-shift transition state, and the isomer CH₂OH₂, while the lower panels show the structures of the methanol ion, its hydrogen-shift transition state, and the isomer CH₂OH₂⁺. Bond distances are in Å and bond angles are in degrees. The numbers outside of and in parentheses are the relative energies in kcal mol^-1 obtained with the CCSD(T) and B3LYP methods.
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In the text

$\begin{figure} \par\includegraphics[width=10cm,clip]{0762fig3.eps} \end{figure}$ Figure 3: Transition state structures for studied reactions calculated at the B3LYP/6-311G(d, p) level, except for TS1, which is calculated at the HF/6-311G(d, p) level. Bond distances are in Å and bond angles are in degrees.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig4.eps} \end{figure}$ Figure 4: Potential energy surfaces of the reactions between CH₃OH and H atoms calculated with the CCSD(T)/aug-cc-pVTZ method. The energy of TS1 (dashed line) is calculated with CCSD(T) method at the geometry obtained with the HF/6-311G(d, p) method. The values in parentheses are the relative energies obtained with the B3LYP/6-311G(d, p) method.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig5.eps} \end{figure}$ Figure 5: Potential energy surfaces of the reaction between CH₃OH₂⁺ and H atoms calculated with the CCSD(T)/aug-cc-pVTZ method. The values in parentheses are the relative energies obtained with the B3LYP/6-311G(d, p) method.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig6.eps} \end{figure}$ Figure 6: Potential energy surfaces of CH₃OH₂⁺ ( upper curve) and its neutralized species ( lower curve) calculated by using the CCSD(T)/aug-cc-pVTZ method at the optimized geometries obtained with the B3LYP/6-311G(d, p) method. The relative energies are shown in kcal mol^-1. The values in parentheses are the calculated relative energies with the B3LYP/6-311G(d, p) method. Bond distances are in Å and bond angles are in degrees.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.1cm,clip]{0762fig7.ps} \end{figure}$ Figure 7: Fractionation ratios of deuterated methanols to normal methanol plotted vs. time for a protostellar source. Lines in black are for the observed species. T=50 K, $n({\rm H_2}$ ) = 10⁶ cm^-3.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{0762fig8.ps} \end{figure}$ Figure 8: As in Fig. 7, except that T=100 K, and $n({\rm H_2}$ ) = 10⁷ cm^-3.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8cm,clip]{0762fig9.ps} \end{figure}$ Figure 9: As in Fig. 8, but using initial abundances from Table 5.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig1.eps} \end{figure}$	Figure 1: Optimized structures of transition states for the synchronous hydrogen-exchange reaction in methanol (H-H exchange TS) and in protonated methanol (H-H exchange TSH⁺) obtained with the B3LYP method. Bond distances are in Å and bond angles are in degrees. The relative transition state energies with the CCSD(T) method are +148.6 kcal mol^-1 for TS and +148.9 kcal mol^-1 for TSH⁺.
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$\begin{figure} \par\includegraphics[width=10cm,clip]{0762fig3.eps} \end{figure}$	Figure 3: Transition state structures for studied reactions calculated at the B3LYP/6-311G(d, p) level, except for TS1, which is calculated at the HF/6-311G(d, p) level. Bond distances are in Å and bond angles are in degrees.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig4.eps} \end{figure}$	Figure 4: Potential energy surfaces of the reactions between CH₃OH and H atoms calculated with the CCSD(T)/aug-cc-pVTZ method. The energy of TS1 (dashed line) is calculated with CCSD(T) method at the geometry obtained with the HF/6-311G(d, p) method. The values in parentheses are the relative energies obtained with the B3LYP/6-311G(d, p) method.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0762fig5.eps} \end{figure}$	Figure 5: Potential energy surfaces of the reaction between CH₃OH₂⁺ and H atoms calculated with the CCSD(T)/aug-cc-pVTZ method. The values in parentheses are the relative energies obtained with the B3LYP/6-311G(d, p) method.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.1cm,clip]{0762fig7.ps} \end{figure}$	Figure 7: Fractionation ratios of deuterated methanols to normal methanol plotted vs. time for a protostellar source. Lines in black are for the observed species. T=50 K, $n({\rm H_2}$ ) = 10⁶ cm^-3.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{0762fig8.ps} \end{figure}$	Figure 8: As in Fig. 7, except that T=100 K, and $n({\rm H_2}$ ) = 10⁷ cm^-3.
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$\begin{figure} \par\includegraphics[angle=-90,width=8cm,clip]{0762fig9.ps} \end{figure}$	Figure 9: As in Fig. 8, but using initial abundances from Table 5.
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