Resource molecule

In captured form and often with bonds broken open they are called moieties.

Basic resource molecules

For mechanosynthesis of diamond ethyne C₂H₂ methane CH₄ and traces of digermane Ge₂H₆ can be used. This has been toroughly analyzed.

Further molecules of prime interest are carbon dioxide CO₂ water H₂O and nitrogen gas N₂. The capability of handling those allows for tapping the air as a resource for products that (almost) exclusively contain diamondoid molecular elements out of hydrogen carbon oxygen and nitrogen (HCON).

From the metals Aluminum and Titanium would be of interest.

Resource molecules for other elements

They should preferentially be non or at least low toxic and easy to handle.

• for boron: B₂H₆ diborane is toxic and reacts with water to
  B(OH)₃ boric acid which is pretty harmless and thus a better resource
• for fluorine: SF₆ sulfur hexafluoride very heavy pretty inert gas, soluble in ethanol
  the sulfur can be used or disposed as diluted sulfuric acid
• for aluminum: ?
• for silicon: silicic acid self polymerizes and is thus not suitable
  SiH₄ [1] seems better but it's quite toxic, higher silans tend to be explosive
• for chlorine: ammonium chloride (salmiak) - or diluted hydrochloric acid - dissolved table salt NaCl if theres use for sodium

Sources for phosphorus

• for phosphorus: PH₃ phosphine seems too toxic
  H₃O₄P phosphoric acid seems good
• ammonium phosphate compounds - (wikipedia)

Sources for sulfur

Good information resource for sulfur compounds: wikipedia

of main interest

• ammonium sulfate (NH₄)₂SO₄ (wikipedia) - pro: waste nitrogen can go to atmosphere, massively available - con: explosive in dry form
• methylsulfonylmethane C₂H₆O₂S- (wikipedia) - pro: non toxic - con: carries carbon too
• sulfuric acid H₂SO₄ (wikipedia) - pro: massively available - con: acidity

maybe interesting

• diallyl trisulfide C6H10S3 (wikipedia) - main component of garlic oil - con: carries lots of carbon and hydrogen
• syn-Propanethial-S-oxide C3H6OS (wikipedia) - irritant expelled by cut onions
• dimethyl trisulfide C2H6S3 (wikipedia)
• carbon disulfide CS₂ (wikipedia) - soluble in ethanol - pro: massively available - con: toxic
• carbonyl sulfide (wikipedia) - con: toxic, carries less sulfur than carbon disulfide
• hydrogen sulfide H2S, sulfur dioxide SO2, sulfur trioxide SO3 - all too dangerous and toxic
• thioacetic acid C2H4OS (wikipedia)
• methanesulfonic acid CH3SO3H (wikipedia), (wikipedia)

Notes

If the non metal element in question is poisonous or unstable with the bonds just capped with hydrogen the oxygen acids of the element may be a better choice. To reduce acidity but not introduce metal cations that would in many cases remain as waste the ammonium cation (wikipedia) can be used.

Silicon is troublesome since most of its compound tend to polymerize instead of staying as separate molecules.

Related

• oddball compounds