Table 2. Vibrational wavenumbers of the HNC⁺ electronic ground state.

Mode	Wavenumber / cm−1	Method	Ref.
ν1	3470	calc.	this work
	3404	calc.	25
	3464	calc.	24
	3365.0	exp.a	52
ν2	605	calc.	this work
	523	calc.	25
	618	calc.	24
	577.7 or 584.5b	exp.a	52
ν3	2260	calc.	this work
	2163	calc.	25
	2212	calc.	24
	2260	exp.	this workc
	2195.2	exp.a	52

^aMeasured in neon matrix.

^bObserved but not assigned to ν₂ by the authors. The NIST recommends 577.7 cm⁻¹.⁵³

^c±80 cm⁻¹.