  We calculate the $\Lambda_c\bar{\Lambda}_c$ partial decay width of the
excited vector charmonium states around 4.6 GeV with the quark pair creation
model. We find that the partial decay width of the $\Lambda_c\bar{\Lambda}_c$
mode can reach up to several MeV for $\psi(4S,~5S,~6S)$. In contrast, the
partial $\Lambda_c\bar{\Lambda}_c$ decay width of the states $\psi(3D,~4D,~5D)$
is less than one MeV. If the enhancement $Y(4630)$ reported by the Belle
Collaboration in $\Lambda_c\bar{\Lambda}_c$ invariant-mass distribution is the
same structure as $Y(4660)$, the $Y(4660)$ resonance is most likely to be a
$S$-wave charmonium state.
