The 637- and 723-keV states in ${\mathrm{Xe}}^{131}$ have been investigated by employing the technique of nuclear resonance fluorecence. The angular distribution of the resonantly scattered radiation from the 637-keV level is consistent with the assignment of either spin and parity ${\frac{5}{2}}^{+}$, decaying to the ground state predominantly by an $M1\mathrm{}$ transition, or a spin and parity of ${\frac{7}{2}}^{+}$ with the decay to the ground state being pure $E2\mathrm{}$. Considering the results of other investigators, a ${\frac{7}{2}}^{+}$ assignment appears to be the correct choice. Assuming a spin of $\frac{7}{2}$, the mean life of the 637-keV level is found to be 1.8 ± 0.8 psec. The fact that resonant scattering from the 723-keV level was observed with a source of gaseous ${\mathrm{II}}^{131}$ is attributed to Coulomb fragmentation of the ${\left({\mathrm{IXe}}^{131}\right)}^{+}$ molecular ion formed following the $\beta$ decay of ${\mathrm{I}}^{131}$. The angular distribution of the resonantly scattered 723-keV $\gamma$ rays is consistent with a spin and parity assignment of ${\frac{5}{2}}^{+}$ to this level, and a pure $M1\mathrm{}$ decay to the ground state. Our results indicate that the mean life of the 723-keV level is greater than 1.5 psec.

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