New Mass Value forLi7

A high-accuracy mass measurement of $^{7}\mathrm{Li}$ was performed with the SMILETRAP Penning-trap mass spectrometer via a cyclotron frequency comparison of $^{7}\mathrm{Li}^{3+}$ and $\mathrm{H}_{2}{}^{+}$. A new atomic-mass value of $^{7}\mathrm{Li}$ has been determined to be $7.016\text{ }003\text{ }425\text{ }6(45)\text{ }\text{ }\mathrm{u}$ with a relative uncertainty of 0.63 ppb. It has uncovered a discrepancy as large as $14\ensuremath{\sigma}$ ($1.1\text{ }\text{ }\ensuremath{\mu}\mathrm{u}$) deviation relative to the literature value given in the Atomic-Mass Evaluation AME 2003. The importance of the improved and revised $^{7}\mathrm{Li}$ mass value, for calibration purposes in nu…