$B(E2,4\to 2)/B(E2,2\to 0)$ ratio in even-even nuclei: Apparent anomalous behavior of the chromium isotopes

We consider the ratio $\mathrm{RE}4=B(E2,4\to 2)/B(E2,2\to 0)$ for the lowest $2^{+}$ and $4^{+}$ states in even-even nuclei. In the rotational and vibrational models and the shell-model calculations considered here, $\mathrm{RE}4$ is greater than 1; however, empirically, using National Nuclear Data Center adopted half-lives and energies for ${}^{48}\mathrm{Cr}$ and ${}^{50}\mathrm{Cr}$, this ratio is less than 1.