Bulk synthesis of a-SixNyH and a-SixOy straight and coiled nanowiresElectronic supplementary information (ESI) available: Movies taken using a microscope. File RI19, shows a white fringe (Becke Line), which surrounds the particle, shift into the particle when the lens is moved farther away from focus. This indicates that the RI of the particle is greater than the surrounding calibration solution (RI = 1.9). Files RI21 and RI23 show the Becke line moving from the particle into the surrounding indicating that the RI of the particle is lower than its surrounding RI of 2.1 and 2.3 respectively. See http://www.rsc.org/suppdata/jm/b3/b311887h/