Optical reflectors for spectrometer gas cells

A spectrometer cell having an internal volume for containing a sample gas, the spectrometer cell comprising:

• a spacer, the spacer at least partially defining the internal volume and comprising a first contact end;
• an end cap, the end cap positioned proximate to and contacting the first contact end and at least partially enclosing the internal volume;
• and
• a mirror, the mirror comprising a reflective surface for receiving and redirecting a beam of light at least once along an optical path length that originates from at least one light source, the reflective surface having an optical axis, the optical path length passing at least once through the internal volume, the mirror being secured in place by a mechanical attachment comprising attachment materials that are chemically inert to at least one reactive gas compound, the mechanical attachment holding the optical axis in a fixed orientation relative to other components of the spectrometer cell and of a spectrometer device that comprises the spectrometer cell.