Table 4. Quantification of the temperature influence on ν ₁ -CO₃ ²⁻ Raman shift based on previous references.

Sources	[CO32−]	P/MPa	Fitting equation (ν1066 = a·T + b)		R2	Standard error
	mol·L−1		∂ν/∂T	Intercept		cm−1
Frantz15 a	1.0	100	−0.0452	1072.4	0.997	0.14
	1.0	150	−0.0446	1072.7	0.997	0.13
	1.0	200	−0.0440	1072.9	0.997	0.12
Martinez et al.21 b	2.0	1000	−0.0411	1072.8	0.97	n.d.

ν₁₀₆₆ is in cm⁻¹. It is the carbonate Raman shift under a constant pressure P (MPa). T is temperature in °C, and its value ranges ^a from 24 to 550 °C, and ^b from 100 to 275 °C. The standard deviations for the slope and the intercept are not determined.

^aPotassium carbonate solution.

^bSodium carbonate solution; n.d. indicates that the value is “not determined”.