Fig. 7
Ab initio XAS of Li2O2 as a function of O–O separation. Experimental and calculated XAS of a relaxed Li2O2 crystal in the Foeppl structure89 (middle) with an O–O bond length of 1.55 Å, and calculated spectra of an artificial planar Li2O2 molecule (right) with various bond lengths. The molecule was first allowed to relax, yielding the 1.57 Å O–O bond length, which was then stretched artificially to create the subsequent molecular structures. Ab initio XAS was performed in the spin polarized DFT-XCH framework, as described previously90
