Bismuth-and indium-based complex oxides, i.e., oxides containing multiple metal cations, are important functional inorganic materials with a central role in many optoelectronic and energy-related applications. Tin-doped bixbyite indium oxide (In 2 O 3 ) is an n-type transparent conducting oxide used in display technology, electrochromic smart windows, and photovoltaics . Complex indium-containing oxides are being developed for the next generation of electronic materials. Lithium indium oxides have been studied as prospective solid electrolytes for all-solid-state lithium-ion batteries. Substituted versions of fluorite bismuth oxide (-Bi 2 O 3 ) and Aurivillius-type mixed-metal bismuth oxides host some of the highest known high oxygen-ion conductivities. Bismuthate glasses are non-toxic candidates to replace lead oxide in zero-stress optic materials. The stereochemically active lone pair in Bi 3+ can lead to noncentrosymmetric structures with useful optoelectronic and ferroic properties. Given the range of technological applications and frequently cation-mixed and/or poorly diffracting nature of bismuth and indium oxides, it is desirable to develop alternative metrologies to study their atomic environments. In and Bi solid-state nuclear magnetic resonance (NMR) spectroscopy could, in principle, offer additional insights into the local coordination, symmetry, and ionic/polyhedral dynamics. The quadrupolar interaction, specifically, yields information on the spherical (C Q ) and axial ( Q ) symmetry. Both nuclei are spin 9/2 with moderate gyromagnetic ratios ( ❑ ¿ 115 = 5.8972  10 7 rad s -1 T -1 ; ❑ Bi 209 = 4.3750  10 7 rad s -1 T -1 ), large nuclear electric quadrupole moments ( Q ¿ 115 = 77.2(5) fm ; Q Bi 209 = -51.6(2) fm 2 ), and high natural abundances ( 115 In = 95.71%; 209 Bi = 100%). Note that In is also spin 9/2 with nearly identical nuclear properties ( ❑ ¿ 113 = 5.8845  10 7 rad s -1 T -1 ; Q ¿ 113 = 76.1(5) fm 2 ); however, it comprises only 4.29% natural abundance and is thus disfavored. An analogy must be drawn to Nb, the only other stable, odd-proton I = 9/2 nucleus (nota bene, there are several odd-neutron I = 9/2 nuclides- Ge, Kr, Sr, and Hf -but these have substantially lower gyromagnetic ratios). Nb has found wider use than its (113)/115