Materials selection, synthesis, characterization, and high-pressure PCT measurements. AB 2 alloys, particularly in the composition space of Ti(Cr, Mn, Fe) 2 , have been extensively studied as potential high-pressure compression materials since specific regions of this ternary B space can yield very large plateau pressures (e.g., ln(P o eq /P o ) ≳ 6). For example, Ti 1.02 Cr 1.1 Mn 0.3 Fe 0.6 demonstrates a ∆H d = 16.5 kJ mol -1 and ∆S d = 103.8 kJ mol -1 , maintains relatively flat plateau with small hysteresis, and exhibits faster hydrogen absorption kinetics upon small amounts of rare earth addition with minimal effect on hydride thermodynamics. For example, a small modification to Ti 1.02 Cr 1.1 Mn 0.3 Fe 0.6 La 0.03 (hereon referred to as "base TCMFL") induces a negligible change in the thermodynamics and exhibits ∆H d = 16.6 kJ mol and ∆S d = 104.2 kJ mol -1 , while substitution with Ce or Ho instead of La yields slightly larger ∆H d . We therefore chose TCMFL as a base material to test our ML-destabilization design rules (Table ), choosing a small amount of Co substitution for Mn: Ti 1.02 Cr 1.1 Mn 0.2 Co 0.1 Fe 0.6 La 0.03 (hereon referred to as "modified TCMCFL").