$.$ Within the Born$-$Oppenheimer approxima$8$on$,$ the poten$8$al energy surface is independent of

isotopic subs$8$tu$8$on$.$ Given that the dissocia$8$on energy for H $2$ is $\%=4\mathrm{.}46$ and that the

fundamental vibra$8$onal frequency $$ is $1\mathrm{.}3210$&$\text{'}"$& $,$ calculate $\%$ and $$ for deuterium, D $2.$

Realize that the observed dissocia$8$on energy is given by

$\%=(1$

$2$

where $($ is the value of $()$ at $()$