Finding min cost is easy: You need 2 glyphs, a triplex, a bonder, and a 2 length arm on a 4 long track to access the dispersion, adding up to a nice and low 110g. Actually creating a solution using only these parts is a whole different story.
First things first, you get quintessence as an input, but the output only uses fire atoms. Welp, just make a wastechain, no problem! 
The much bigger concern is the triplex bonds you need to create. In order to create the zigzag of fire atoms in the product without making any accidental triplex bonds, you need your polymer to kiss the triplex on all 6 sides (technically a triplex has only 3 sides, but you need to angle your polymer to the right and to the left of each side for different fire atoms, so each side is used in 2 different ways). This results in a region I'm calling THE DEATH STAR, represented in my solution by equilibrium atoms placed in a 4 hex wide line in each direction starting at the triplex bonder. 
Rule 1 of THE DEATH STAR: You cannot place any inputs inside of THE DEATH STAR (the reactive iron can be placed halfway inside of it, but i didn't utilize that). 
Rule 2 of THE DEATH STAR: The track the arm is on cannot be contained entirely within 1 of the 6 branches of THE DEATH STAR. 
If either of these 2 rules are not followed, you will end up in a situation where if you try to place your molecule in one of the 6 triplexing spots, it will result with a collision with an input atom or your arm will have nowhere to go while bonding.
These limitations heavily restrict you on what layout you're allowed to use to get min cost. Lets be honest, no sane person would ever use a 4 long line shaped track to access a dispersion glyph instead of a pretty loop de loop, but in this puzzle such a track shape is necessary.
One final problem you may encounter (if you're smart and know how to think forward that is, personally I encountered a dozen more entirely avoidable problems) is where to put the wastechain while bonding. Unlike the input atoms, you are allowed to move it around while solving so it isn't as restrictive, but given how cramped the layout you still need to pay attention, or you'll end up in an unsolvable state. I opted in to suppress the reactive iron input with the waste chain to reuse that space, as there wasn't any other valid locations.
Oh, and don't forget, the secondary is instructions!!! Don't forget about instructions!!! We alllllll love instructions don't we folks!!!
Yeah, you have to 1/2p the solve too, and yes, it is a pain in the ass. In fact, this single set of instructions doesn't even account for 2 parallel universes, it accounts for 5 separate ones! During one half of the solve, there's special casing for the 1st period, the 2nd+3rd period, and the 4th period onward, and then during the other half there's special casing for every even-numbered period and every odd-numbered period. The monomer the output is constructed out of can alllllllmost be split in half, except for the reactive iron attachment at the bottom, so during half of the periods, the arm conditionally grabs the polymer's front quicksilver, pulls the polymer away, and doesn't attach a reaction iron, and during the other half of periods it fails to conditionally grab, and then attaches a reactive iron. The 1st/2nd/3rd period conditionals are necessary because during the first few periods the monomer isn't long enough yet to grab it efficiently, so first the arm pretends it grabbed a period 4+ monomer, and then later comes back and resyncs the timeline during from the first few periods, which it failed to grab. The 2nd and 3rd period are similar enough that a single set of backup instructions is enough to handle them both.
So yeah, quite a lot going on in this puzzle. The track layout, the glyph layout, the weird triplex usage, the waste chain, THE DEATH STAR, the input suppression using the waste chain to occupy as little of THE DEATH STAR as possible... I didn't even mention how i figured out a good layout, coded 200 instructions, realized the regular bonder was in a bad place, coded 250 new instructions, realized that the bonder is in a bad place AGAIN except slightly less trivially this time and there wasn't a single valid spot for the bonder anywhere in the layout so I had to flip the entire layout horizontally and start from scratch, code 300 more instructions, and have a brief heart attack because i forgot to place the projection, quickly followed by the world's biggest sigh of relief because there was exactly 1 possible spot where it could be placed. 
This solution, despite being so overexplained, isn't very optimized aside from being 1/2p, so I'm only going to get 6th place or something (because holy fuck, there's a lot of talented people in this community). I don't blame anyone who didn't manage to get min as it was pretty difficult, but I managed to pull through because there's no greater feeling than finally completing your instruction tray, putting that reset instruction at the end, then pressing play and putting your hands behind your back, watching your creation you spent at least 6 hours upon come to life. It's enough to make a grown man cry. 
Special thanks to: Ms-Paint for being a moderately good sketching tool despite not having good rotation features, Aseprite for being a slightly better sketching tool despite lagging a ton while rotating things, and also the scaffolding mod for easy testing of different parallel universes (without it, I'd still be debugging this shit) Good luck everyone, and have a wonderful day