Trilithium
Trilithium was a compound that, as of 2371, was experimental. By 2373, it was carried on some Federation starships. Trilithium was a nuclear inhibitor which could stop all fusion within a star by way of quantum implosion. (; )

Dilithium and paralithium could both be converted into trilithium, while the explosion of trilithium might result in trilithium resin, a highly toxic substance that could also be used as a weapon. (; ; ) A trilithium signature might show up in the theta-band. ()

History
As of the early 2370s, Starfleet was aware that the Romulans had been working on trilithium, but had not found a way to stabilize it. Some Romulan trilithium was stolen in a raid by the Duras sisters, who were contracted to deliver it to Dr. Tolian Soran, in exchange for a functional trilithium-based weapon. Soran used the trilithium to collapse the star Amargosa, in an effort to change the course of the Nexus ribbon. He planned to do the same to the star Veridian, as he added the cloaking device for another trilithium-based solar probe missile on the surface of Veridian III, in which would have destroyed the pre-industrial civilization on Veridian IV. Soran's plans were thwarted by the . ()

A trilithium-based explosive was used by the Akritirian terrorist group Open Sky to bomb the Laktivia recreational facility in 2373. The trilithium used was synthesized from paralithium from an Akritirian freighter. The  was originally implicated in the attack, since there was no source of trilithium present in their system or indeed their sector, but it could be synthesized from dilithium, which powered Voyagers engines. ()

Later that year in the Alpha Quadrant, the  carried trilithium. Captain Benjamin Sisko ordered two quantum torpedos to be outfitted with cargo pods carrying two hundred kilograms of trilithium each, which when detonated in the atmosphere of Solosos III poisoned it with trilithium resin, rendering the planet uninhabitable to Humans for fifty years. ()

Shortly thereafter, the Dominion attempted to detonate a device containing trilithium, tekasite, and protomatter into the Bajoran sun, by way of a Changeling infiltrator hijacking the runabout . At that time, a combined Federation, Klingon, and Romulan fleet was gathered at Deep Space 9 in anticipation of a supposed Dominion attack. The attack was a ruse to wipe out all three fleets and Bajor in a single stroke with the supernova of the Bajoran sun. The Defiant was able to tractor the Yukon away from the sun, and the bomb exploded harmlessly in open space. ()

By 2375, high concentrations of trilithium isotopes indicated the presence of Romulan plasma torpedoes. ()

That same year, the Silver Blood  collected samples of trilithium ore. ()

External link

de:Trilithium
Chemical compounds
Explosives