D4Xgui 1.0.8

Welcome to D4Xgui v1.0.8!

D4Xgui is developed to enable easy access to state-of-the-art CO₂ clumped isotope (∆₄₇, ∆₄₈ and ∆₄₉) data processing. A recently developed optimizer algorithm allows pre-processing of mass spectrometric raw intensities utilizing a m/z47.5 half-mass Faraday cup correction to account for the effect of a negative pressure baseline, which is essential for accurate and highest precision clumped isotope analysis of CO₂ (Bernecker et al., 2023). It is backed with the recently published processing tool D47crunch (v.2.4.3) (following the methodology outlined in Daeron, 2021), which allows standardization under consideration of full error propagation and has been used for the InterCarb community effort (Bernasconi et al., 2021). This web-app allows users to discover replicate- or sample-based processing results in interactive spreadsheets and plots. The Dual Clumped Space page supports Δ₉₅ thermometry (D95eq) for Δ₄₇–Δ₄₈ pairs, including 95% confidence ellipses and equilibrium overlays.

Example data is accessible from the Data-IO page, or can be downloaded from GitHub. Please check INSTALLATION.md to find help setting up D4Xgui.

In order to process post-background corrected data (Data-IO page, Upload δ⁴⁵-δ⁴⁹ replicates tab), the following columns need to be provided (.xlsx, .csv):

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Baseline correction can be performed using a m/z47.5 half-mass cup. For this purpose either a set of equilibrated gases (via heated-gas-line), or carbonate standards (via target values) is used to determine m/z47, m/z48 and m/z49-specific scaling factors. Please upload a cycle-based spreadsheet (.xlsx, .csv) including the following columns (Data-IO page, Upload m/z44-m/z49 intensities tab):

Please find the code documentation here.