Density Functional Theory Study on the Effect of Isomorphic Substitution of FAU Molecular Sieve on N₂ Adsorption Performance

Table 1

Calculated lattice constants, lengths of Al/Si/Zn/Ca/Ga-O bonds, and r_RMS of the different substituted atoms in the Zn/Ca/Ga-doped β-cage and pristine β-cage after optimization.

	Lattice constants/Å	Bond length (Si-O)/Å	Bond length (Al-O)/Å	Bond length (Zn/Ca/Ga–O)/Å	rRMS/Å
Pristine (Al, Si)	25.028	1.661	1.706	—	—
Pristine (Al′, Si′)	25.028	1.618	1.721	—	—
Zn-doping (Al)	25.028	1.601	1.747	1.880	0.11
Zn-doping (Al′)	25.028	1.625	1.762	1.911	0.12
Zn-doping (Si)	25.028	1.585	1.757	1.913	0.15
Zn-doping (Si′)	25.028	1.602	1.750	1.912	0.18
Ca-doping (Al)	25.028	1.591	1.736	2.150	0.26
Ca-doping (Al′)	25.028	1.623	1.770	2.181	0.27
Ca-doping (Si)	25.028	1.645	1.715	2.213	0.32
Ca-doping (Si′)	25.028	1.577	1.778	2.190	0.34
Ga-doping (Al)	25.028	1.604	1.725	2.238	0.31
Ga-doping (Al′)	25.028	1.607	1.715	2.130	0.24
Ga-doping (Si)	25.028	1.635	1.708	1.788	0.08
Ga-doping (Si′)	25.028	1.657	1.710	1.785	0.10