Molecular structure extracted from residual dipolar couplings: Diphenylmethane dissolved in a nematic liquid crystal
2005 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 123, no 4, 044507- p.Article in journal (Refereed) Published
This paper describes an analysis of 1H–1H residual dipolar couplings (RDCs)in diphenylmethane (DPM) dissolved in a nematic liquid crystal, reportedby Celebre et al. [J. Chem. Phys. 118, 6417 (2003)]. Inthat article, the conformational distribution function for DPM was extractedfrom the RDCs, using the additive potential (AP) model whichis based on the molecular-field theory. The AP approach isa powerful, and frequently used, tool for analysis of thenuclear-magnetic-resonance (NMR) parameters in liquid crystals. It requires, however, apriori knowledge of the functional form of the torsional potential,which may even for a simple molecule, such as DPM,be complicated to determine. Here, we analyze the same setof the RDCs using our APME procedure, which is ahybrid model based on the AP approach and maximum entropy(ME) theory. The APME procedure does not require any assumptionsabout the functional form of the torsional potential and, incontrast with the ME method, is applicable to weakly orderedsystems. In the investigation reported in the present study, theresults from the APME analysis are in good agreement withthe AP interpretation, whereas the ME approach essentially fails inthe extraction of the conformational distribution function for DPM.
Place, publisher, year, edition, pages
American Institute of Physics , 2005. Vol. 123, no 4, 044507- p.
nematic liquid crystals, organic compounds, dissolving, dipole coupling, nuclear magnetic resonance, molecular configurations
Research subject Physical Chemistry
IdentifiersURN: urn:nbn:se:su:diva-36820DOI: 10.1063/1.1950629OAI: oai:DiVA.org:su-36820DiVA: diva2:290472