Carbon atomic number Z=6 propagates through a chain of physical necessities governing every scale of CO2 capture chemistry. We trace this chain from nuclear structure through molecular geometry to crystallographic coordination (MOF-74 metal nodes all CN=6 octahedral). The ultimate n=6 equation is photosynthesis: 6CO2+6H2O→C6H12O6+6O2. We design an 8-level capture architecture (HEXA-CCUS) and perform design space exploration of 1,360,800 combinations, yielding 54 Pareto-optimal solutions all achieving n6=100%. Honest assessment: 20 physical necessities (90% EXACT), 7 design choices (all WEAK), 2 HONEST FAILs.
TECS-L Research Group (Thu,) studied this question.