The Oxygen-K edge of the energy loss near-edge structure (ELNES) spectrum of the pure W-18O49 phase was acquired and compared with DFT calculations (Figure ). To collect the ELNES data for the W18O49 lattice, the focused beam was scanned through the entire area marked by the lower yellow square on the cross-section (Fig. ). This procedure ensured that the measurement was taken from a domain consisting entirely of a W18O49 phase. Other suboxide phases in the material could alter the spectrum when observed from a regular nanowhisker, especially when viewed perpendicularly to the <010> axis. The complexity of the W18O49 lattice could be described in terms of different types of tungsten and oxygen atoms in the structure. Specifically, each of the oxygen lattice sites and its coordination contributes differently to the oxygen-K edge ELNES. The W18O49 lattice is monoclinic (point group P2/m).