  Magneto transmission spectroscopy was employed to study the valley Zeeman
effect in large-area monolayer MoS$_{2}$ and MoSe$_{2}$. The extracted values
of the valley g-factors for both A- and B-exciton were found be similar with
$g_v \simeq -4.5$. The samples are expected to be strained due to the CVD
growth on sapphire at high temperature ($700^\circ$C). However, the estimated
strain, which is maximum at low temperature, is only $\simeq 0.2\%$.
Theoretical considerations suggest that the strain is too small to
significantly influence the electronic properties. This is confirmed by the
measured value of valley g-factor, and the measured temperature dependence of
the band gap, which are almost identical for CVD and mechanically exfoliated
MoS$_2$.
