TY - JOUR
T1 - Vibrational study and spectra-structure correlations in ammonium saccharinate
T2 - Comparison with the alkali saccharinates
AU - Naumov, Panče
AU - Jovanovski, Gligor
N1 - Funding Information:
The authors are grateful to Dr O. Grupče for recording the Raman spectra, to S. Abbrent (Inorganic Chemistry, University of Uppsala) for the DSC measurements and to Dr S.W. Ng (Institute of Postgraduate Studies and Research, University of Malaya) for providing the structural data of AMS. The financial help from the Ministry of Science of the Republic of Macedonia is gratefully acknowledged.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2000/6
Y1 - 2000/6
N2 - The FT IR spectra, at temperatures from liquid-nitrogen boiling (LNT) up to room temperature (RT), as well as the RT Raman solid-state spectra of protonated and deuterated ammonium saccharinate and of a series of alkali (Na, K, Rb, Cs) saccharinates are studied. The spectral assignments are aided with ab initio calculations on the free saccharinato anion at the HF/6-31++G(d,p) level. Attention is paid to the ND, CO and SO2 stretching regions. Correlation splitting is believed to be responsible for the presence of a v(CO) doublet. The averaged v(CO) frequency in (purely ionic) ammonium saccharinate is found to be the lowest in the so far studied saccharinates, along with the assumptions that the v(CO) frequency (or the corresponding averaged value) can have predictive value for the type of the metal-to-saccharinato ligand/ion bonding. The appreciably higher contribution of the dominating internal coordinate in the corresponding normal vibration in case of vas(SO2) than in vs(SO2) makes it suitable for spectra-structure correlations. Contrary to RT, even though no phase transitions were observed in the studied temperature range, some polycentered character is prescribed to the hydrogen bonds in which the ammonium ions of effective symmetry Cs participate at LNT. Certain structural predictions about the saccharinates of K, Rb and Cs are made.
AB - The FT IR spectra, at temperatures from liquid-nitrogen boiling (LNT) up to room temperature (RT), as well as the RT Raman solid-state spectra of protonated and deuterated ammonium saccharinate and of a series of alkali (Na, K, Rb, Cs) saccharinates are studied. The spectral assignments are aided with ab initio calculations on the free saccharinato anion at the HF/6-31++G(d,p) level. Attention is paid to the ND, CO and SO2 stretching regions. Correlation splitting is believed to be responsible for the presence of a v(CO) doublet. The averaged v(CO) frequency in (purely ionic) ammonium saccharinate is found to be the lowest in the so far studied saccharinates, along with the assumptions that the v(CO) frequency (or the corresponding averaged value) can have predictive value for the type of the metal-to-saccharinato ligand/ion bonding. The appreciably higher contribution of the dominating internal coordinate in the corresponding normal vibration in case of vas(SO2) than in vs(SO2) makes it suitable for spectra-structure correlations. Contrary to RT, even though no phase transitions were observed in the studied temperature range, some polycentered character is prescribed to the hydrogen bonds in which the ammonium ions of effective symmetry Cs participate at LNT. Certain structural predictions about the saccharinates of K, Rb and Cs are made.
UR - http://www.scopus.com/inward/record.url?scp=0033623727&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033623727&partnerID=8YFLogxK
U2 - 10.1016/S1386-1425(99)00229-2
DO - 10.1016/S1386-1425(99)00229-2
M3 - Article
C2 - 10888436
AN - SCOPUS:0033623727
SN - 1386-1425
VL - 56
SP - 1305
EP - 1318
JO - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
JF - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
IS - 7
ER -