Chromium is one of the essential commodities for today's life, with applications in stainless and high-alloy steels, providing enhanced corrosion resistance and improved mechanical properties. Chromium is usually added to the steel in the form of ferrochrome (FeCr) alloy. The 'Ring of Fire' chromite deposit in northern Ontario presents an opportunity for Canada to enter the globally strategic market. It contains the only commercial quantities of chromite in North America and is the fourth largest deposit in the world. The resources, including Measured, Indicated, and Inferred, are 300 Mt grading approximately 33% Cr 2 O 3. However, the remote location of the deposits makes development challenging. The preference for processing the chromite ore to marketable ferrochromium alloy within Ontario constitutes an additional challenge due to high electricity costs. Currently, 80% of the world's FeCr is produced in submerged arc furnaces. There are four technologies currently used for the production of ferrochrome alloys. These are chromite, ferrochrome, prereduction, direct reduction, catalysts, Ring of Fire.

We report herein the linear optical properties of some extended 2,4,6-triphenyl-s-triazines of formula 2,4,6-[(1,4-C6H4)C≡C(4-C6H4X)]3-1,3,5-(C3H3N3) (3-X; X = NO2, CN, OMe, NMe2, NPh2) and related analogues 4 and 7-X (X = H, NPh2), before briefly discussing their two-photon absorption (2PA) cross-sections. Their 2PA performance is discussed in relation to 2PA values previously measured for closely related octupoles such as N,N′,N″-triphenylisocyanurates (1-X, 5, and 6-X) or 1,3,5-triphenylbenzenes (2-X). While s-triazines are usually much better two-photon absorbers in the near-IR range than these molecules, especially when functionalised by electron-releasing substituents at their periphery, they present a decreased transparency window in the visible range due to their red-shifted first 1PA peak, in particular when compared with corresponding isocyanurates analogues. In contrast, due to their significantly larger two-photon brilliancy, 2,4,6-triphenyl-s-triazines appear more promising than the latter for two-photon fluorescence bio-imaging purposes. Rationalisation of these unexpected outcomes is proposed based on DFT calculations.