Extremophiles maintain an active metabolism up to 122 °C (Takai et al. 2008). These extreme conditions are found, for example in hot springs, in deep oceanic and crustal sediments and in hydrothermal vents at mid-oceanic spreading ridges (Edwards et al., 2011; Heuer et al., 2020). Several studies have investigated the diversity of microorganisms and their relationship to the geological environment as well as to responses to changes. However, the physicochemical parameters necessary to sustain metabolism under these conditions, including the stability of essential molecular compounds like adenosine triphosphate (ATP) and adenosine diphosphate (ADP) have been only studied marginally.

Adenosine triphosphate and adenosine diphosphate are essential energy stores in all currently known metabolic systems. In living cells, the energy is released by the enzymatically controlled exergonic hydrolysis of ATP to power other vital endergonic processes. The abiotic hydrolysis of ATP is kinetically enhanced at elevated temperatures and low pH values resulting in a very short lifetime of ATP and ADP in aqueous solutions (Hulett 1970; Khan and Mohan 1974; Leibrock et al. 1995). Therefore, the kinetic stability of ATP plays a crucial role in metabolism at extreme temperatures. This aspect has been proposed as a critical factor in determining the limits of living cells (Bains et al. 2015).

This data publication compromises all Raman spectra obtained for solutions of Na2ATP with an initial pH of 3 and 7 at 80 °C, 100 °C and 120 °C and for solutions of Na2ADP with initial pH 5 at 100 °C and 120 °C. A hydrothermal diamond anvil cell (HDAC) coupled to a Raman spectrometer was used for in-situ measurements. Pressure was estimated from the vapor-liquid curve of water. In addition to the Raman spectra, the following data are provided: an assignment of peaks in the fitted spectral range, the initial fit parameters, and the fit results.