Loading…
Development of a quantum cascade laser absorption spectrometer for simultaneous measurement of 13 C- 18 O and 18 O- 18 O clumping in CO 2
Dual clumped isotope paleothermometry determines carbonate formation temperatures by measuring the frequency of C- O (∆ ) and O- O (∆ ) pairs in carbonates. It resolves isotopic kinetic biases and thus enables more accurate paleotemperature reconstructions. However, high-precision measurements of O-...
Saved in:
| Published in: | Rapid communications in mass spectrometry 2024-08, Vol.38 (16), p.e9836 |
|---|---|
| Main Authors: | , , , |
| Format: | Article |
| Language: | English |
| Citations: | Items that this one cites |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Dual clumped isotope paleothermometry determines carbonate formation temperatures by measuring the frequency of
C-
O (∆
) and
O-
O (∆
) pairs in carbonates. It resolves isotopic kinetic biases and thus enables more accurate paleotemperature reconstructions. However, high-precision measurements of
O-
O clumping using current techniques requires large sample sizes and long acquisition times.
We developed a mid-infrared isotope ratio laser spectrometer (IRLS) for simultaneous measurement of the isotopologue ratios ∆
and ∆
in gas-phase carbon dioxide (CO
) at room temperature. Our IRLS uses a single laser scanning from 2290.7 to 2291.1 cm
and a 31 m pathlength optical cell, and it simultaneously measures the five isotopologues required for calculating ∆
and ∆
:
O
C
O,
O
C
O,
O
C
O,
O
C
O, and
O
C
O. In addition, our IRLS can measure
O
C
O, enabling ∆
O analysis.
At ~20°C and a CO
pressure of ~2 Torr, our IRLS system achieved precisions of 0.128‰ and 0.140‰ within 20 s for abundances of the clumped isotopologues
O
C
O and
O
C
O, respectively, and precisions of 0.267‰, 0.245‰, and 0.128‰ for
O
C
O,
O
C
O, and
O
C
O. This yielded precisions of 0.348‰ (∆
) and 0.302‰ (∆
) within 25 s. Simulated sample-reference switching highlights the potential of our system and the need for further development.
We demonstrated simultaneous measurements of ∆
and ∆
in CO
to precisions of |
|---|---|
| ISSN: | 0951-4198 1097-0231 |
| DOI: | 10.1002/rcm.9836 |