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We report the 488 nm photoelectron spectrum of the NbCr$\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ anion. For the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Delta$ ground state of neutral NbCr, the short bond length (1.894 \AA) and high bond energy (D$0$ 3.0263(6) eV) measured by R2PI spectroscopy indicate high order multiple bonding. We find that the NbCr$\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ anion has a $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Sigma +$ ground state, in which the "extra" electron occupies the (4d)$\delta$ bonding orbital, giving a $1\sigma 21\pi 41\delta 42\sigma 2$ valence electron configuration and a formal bond order of 6. Low-lying excited states of NbCr (assigned as two $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma +$ states) and NbCr$\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ ($\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Delta$) are also observed. The spectra provide the electron affinity of NbCr, energies of the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma +$ and the $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Delta$ excited states, vibrational frequencies for the NbCr and NbCr$\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ ground states and for the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma +$ excited states, and (from Franck-Condon analyses) differences among the bond lengths of the observed states. These results are compared with our previous data for the Group 5/6 congeners NbMo, VCr, and VMo, and with DFT predictions. We also report results for ongoing experiments on the flow tube reactions of the Group V metals Nb and Ta with butadiene, and the vibrationally-resolved photoelectron spectra of some of the organometallic reaction product anions.