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We have identified two new near-infrared emission lines in the spectra ofplanetary nebulae (PNe) arising from heavy elements produced by neutron capturereactions: [Te III] 2.1019 $\mu$m and [Br V] 1.6429 $\mu$m. [Te III] wasdetected in both NGC 7027 and IC 418, while [Br V] was seen in NGC 7027. Theobservations were obtained with the medium-resolution spectrograph EMIR on the10.4m Gran Telescopio Canarias at La Palma, and with the high-resolutionspectrograph IGRINS on the 2.7m Harlan J. Smith telescope at McDonaldObservatory. New calculations of atomic data for these ions, specificallyA-values and collision strengths, are presented and used to derive ionicabundances of Te$^{2+}$ and Br$^{4+}$. We also derive ionic abundances of otherneutron-capture elements detected in the near-infrared spectra, and estimatetotal elemental abundances of Se, Br, Kr, Rb, and Te after correcting forunobserved ions. Comparison of our derived enrichments to theoreticalpredictions from AGB evolutionary models shows reasonable agreement for solarmetallicity progenitor stars of $\sim$2 - 4 M$_{\odot}$. Thespectrally-isolated [Br V] 1.6429 $\mu$m line has advantages for determiningnebular Br abundances over optical [Br III] emission lines that can be blendedwith other features. Finally, measurements of Te are of special interestbecause this element lies beyond the first peak of the s-process, and thusprovides new leverage on the abundance pattern of trans-iron species producedby AGB stars.

Neutron-Capture elements in planetary nebulae: first detections of near-Infrared [Te III] and [Br V] emission lines