“…On the computational front, using density functional theory (DFT , ) Arroyo-de Dompablo et al spearheaded the investigation (and discovery) of alternative Ca-intercalation chemistries, including oxide (i.e., CaMn 2 O 4 , Ca 2 Mn 2 O 5 , CaMn 4 O 8 , Ca 2 Fe 2 O 5 , Ca 4 Fe 9 O 17 , Ca 3 Co 4 O 9 , and Ca 3 Co 2 O 6 ) and mixed anion (i.e., CaFeSO, CaCoSO, CaNiN, Ca 3 MnN 3 , Ca 2 Fe(Si 2 O 7 ), CaM(P 2 O 7 ) with M = V, Cr, Mn Fe and Co, CaV 2 (P 2 O 7 ) 2 , Ca(VO) 2 (PO 4 ) 2 , and α-VOPO 4 ) frameworks. − For example, they reported a low Ca E m of ∼650 meV in α-VOPO 4 , along with the high theoretical gravimetric capacity (∼312 mAh/g) and average (theoretical) intercalation voltage of ∼2.8 V vs Ca/Ca 2+ , making VOPO 4 a promising candidate for further experimental investigation.…”