- Titel
- Raman Spectroscopic Studies on Aqueous Sodium Formate Solutions and DFT Calculations
- Zitierfähige Url:
- https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa2-910213
- Quellenangabe
- Journal of solution chemistry
Erscheinungsjahr: 2022
Jahrgang: 51
Seiten: 935-961
E-ISSN: 1572-8927 - Erstveröffentlichung
- 2022
- Abstract (EN)
- NaHCOO(aq) and NaDCOO(aq) solutions were measured using Raman spectroscopy from dilute to concentrated solutions at 23 °C in water and heavy water from 50 to 4300 cm−1. A concentrated NaHCOO solution in heavy water was also measured. The Raman band parameters of HCOO−(aq) and DCOO−(aq) such as peak position, full width at half maximum (fwhm), integrated intensities, and depolarization values were determined. From the Raman spectroscopic data, it was concluded that the HCOO−(aq) and DCOO−(aq) symmetry is lower than C2v and probably as low as C1. In contrast to the solution state, (HCO2−(DCO2−) possess C2v symmetry in the gas phase and the DFT frequencies are given. DFT frequencies on a cluster of HCOO−/DCOO− with five implicit water molecules in the first sphere and placed in a polarizable continuum deviate not more than 1–2% from the measured ones. In the Raman spectrum in NaHCOO(aq), a band doublet at 2730 cm−1 and 2820 cm−1 occurs instead of a single band. The band doublet is due to Fermi resonance and results from the interaction of the overtone of the bending C–H mode, 2ν6 at 1382 cm−1 and ν1. The undisturbed C–H stretching mode, ν1 amounts to 2785 cm−1. In DCOO−(aq), a Fermi doublet was also observed at 2030.5 and 2116.5 cm−1, and the undisturbed wavenumber position amounts to 2101 cm−1. Furthermore, a solution of HCOO− in D2O showed slightly changed frequencies compared with the ones in water caused by the solvent isotope effect. Ion pairing between Na+ and HCOO− characterizes the Raman spectrum at high solute concentrations which are melt-like enabling direct contact between the ions. A NaHCOO solution with high amounts of LiCl added showed large perturbations of the HCOO− bands especially νsCOO− and δ COO− of HCOO−and revealed a stronger affinity of Li+ toward HCOO−. The ion pairs formed are most likely contact ion pairs between Li+ and HCOO− which have different stoichiometry of Li+: HCOO− such as 1:1 and 2:1.
- Andere Ausgabe
- Link zum Artikel der zuerst in der Zeitschrift „Journal of solution chemistry” bei Springer Link erschienen ist.
DOI: 10.1007/s10953-022-01170-2 - Freie Schlagwörter (DE)
- Raman-Spektroskopie, NaHCOO- und NaDCOO-Lösungen, Schwingungsnormalmoden, Terahertz-Wellenzahlbereich, DFT-Strukturen und Frequenzberechnungen, PCM-Berechnungen
- Freie Schlagwörter (EN)
- Raman spectroscopy, NaHCOO and NaDCOO solutions, Vibrational normal modes, Terahertz wavenumber region, DFT structures and frequency calculations, PCM calculations
- Klassifikation (DDC)
- 540
- Verlag
- Springer Science + Business Media B.V., New York, NY [u.a.]
- Förder- / Projektangaben
- Deutsche Forschungsgemeinschaft (DFG)
Forschungsgroßgeräte
Compute Cluster zur Zentralisierung der Rechenbedarfe
ID: 397252409 - Version / Begutachtungsstatus
- publizierte Version / Verlagsversion
- URN Qucosa
- urn:nbn:de:bsz:14-qucosa2-910213
- Veröffentlichungsdatum Qucosa
- 22.05.2024
- Dokumenttyp
- Artikel
- Sprache des Dokumentes
- Englisch
- Lizenz / Rechtehinweis
CC BY 4.0