Ground State Tuning by Spin-Orbit Coupling and Lattice Degrees of Freedom in Single-Crystal BaIr$_{\mathrm{1-x}}$Ru$_{\mathrm{x}}$O$_{3}$ (0 $\le $ x $\le $ 1)*

BaIrO$_{3}$ is a magnetic insulator driven by spin-orbit coupling (SOC) whereas BaRuO$_{3}$ is a paramagnetic metal. The contrasting ground states provide a unique opportunity to study the role of the SOC and the lattice degrees freedom. Our investigation reveals that substitution of Ru$^{4+}$ (4$d^{4})$ ions for Ir$^{5+}$ (5$d^{5})$ ions in BaIrO$_{3}$ reduces the magnitude of the SOC and the structural distortion. There are two major effects of Ru additions: (1) Light Ru doping (0$\le $ x $\le $ 0.15) prompts a simultaneous, precipitous drop in both the magnetic ordering temperature T$_{\mathrm{C}}$ and the electrical resistivity, which exhibits a crossover behavior from a metallic to an insulating state near T$_{\mathrm{C}}$. (2) Heavier Ru doping (0.41$\le $ x $\le $ 0.9) induces a robust metallic state with a strong spin frustration.