Converting CO 2 into high-value chemicals has been regardeda sa nimportant solution for as ustainable low-carbon economy.I nt his work, we have theoretically designed an innovative strategy for the absorptiona nd activation of CO 2 by the electride N3Li, that is,1 ,3,5(2,6)-tripyridinacyclohexaphane (N3) intercalated by lithium.D FT computations showed that the interaction of CO 2 with N3Li leads to the catalytic complex N3Li(h 2 -O 2 C), which can initiate the radical-controlled reduction of anotherC O 2 to form organic acids through radical reactions in the gas phase. The CO 2 reductionc onsists of four steps:( 1) The formation of N3Li(h 2 -O 2 C) through the combinationo fN 3Li and CO 2 ,(2) hydrogen abstraction from RH (R = H, CH 3 ,a nd C 2 H 5 )b yN 3Li(h 2 -O 2 C) to form the radical RC and N3Li(h 2 -O 2 C)H, (3) the combination of CO 2 and the radicalRC to form RCOOC,and (4) intermolecular hydrogen transferf rom the intermediateN 3Li(h 2 -O 2 C)H to RCOOC.I nt he whole reactionp rocess, the CO 2 moiety in the complex N3Li(h 2 -O 2 C) maintains ac ertainr adical character at the carbon atom of CO 2 and plays as elf-catalyzing role. This work represents the first example of electridesponsored radical-controlledC O 2 reduction,a nd thus provides an alternative strategy for CO 2 conversion.

There has been growing interest in the CO 2 capture and reduction by transition-metal-free catalysts. Here we performed a proof-ofconcept study using an ab initio valence bond method called the block-localized wave function (BLW) method. The integrated BLW and density function theory (DFT) computations demonstrated that heterobimetallic Ae + /Al(I) (Ae represents alkaline earth metals Mg and Ca) Lewis acid/base combinations without transition metals can facilely capture and activate CO 2 . There are two remarkable findings in this study. The first concerns the ionic nature of the metal−metal bonds. The experimentally synthesized low valent aluminum compound with a bidentate β-diketiminate (BDI) ligand, or (BDI)Al(I) in brief, is a Lewis base due to the lone pair on the aluminum cation though overall Al(I) is positively charged. Al(I) can form ionic metal− metal bonds with the alkaline earth metals of the positively charged Lewis acids (BDI)Ae + . This type of ionic metal−metal bonds is counterintuitive and antielectrostatic as both metals carry positive charges. The second finding is the CO 2 activation mechanism. (BDI)Al(I) can effectively bind and activate CO 2 by transferring one electron to CO 2 , and the resulting complex can be best expressed as [(BDI)Al(I)] + [CO 2 ] − . The participation of (BDI)Ae + further enhances the capture and activation of CO 2 by (BDI)Al(I).

Two advantages of metalloradical: serves as an initiator of CO2 reduction and provides transition metal hydrogen complex (TMHC).

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