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ScCl3 is Bismuth triodide structured and crystallizes in the trigonal R-3 space group. The structure is two-dimensional and consists of three ScCl3 sheets oriented in the (0, 0, 1) direction. Sc3+ is bonded to six equivalent Cl1- atoms to form edge-sharing ScCl6 octahedra. There are three shorter (2.50 Å) and three longer (2.51 Å) Sc–Cl bond lengths. Cl1- is bonded in an L-shaped geometry to two equivalent Sc3+ atoms.
An investigation was conducted of the two reactions: Sc + F2 yields ScF(asterisk) + F and Y + Cl2 yields YCl(asterisk) + Cl. Experiments were designed for studying the reactions under the relatively high pressure conditions (5-20 torr) appropriate for chemical laser operation. A shock tube was used to provide a short duration flow through a supersonic nozzle array. Shock wave heating is used to dissociate the ScCl3 or YCl3 at temperatures of about 6000 K, before the gases are accelerated and expanded through the supersonic nozzle array. The expanded primary flow is then mixed with a secondary flow of F2 introduced through slots at the trailing edge of each nozzle blade. Graphs show the temporal behavior of the visible spontaneous emission over the range from 3000 to 9000 A for a typical test condition, a microdensitometer tracing of the visible emission over the range from 4000 to 7000 A, and the spontaneous emission from ScF(asterisk) obtained by computer image processing of intensity data.