Please use this identifier to cite or link to this item: http://hdl.handle.net/10316/17949
DC FieldValueLanguage
dc.contributor.authorBorba, Ana-
dc.contributor.authorAlbrecht, Merwe-
dc.contributor.authorGómez-Zavaglia, Andrea-
dc.contributor.authorLapinski, Leszek-
dc.contributor.authorNowak, Maciej J.-
dc.contributor.authorSuhm, Martin A.-
dc.contributor.authorFausto, Rui-
dc.date.accessioned2011-12-16T15:34:24Z-
dc.date.available2011-12-16T15:34:24Z-
dc.date.issued2008-10-
dc.identifier.urihttp://hdl.handle.net/10316/17949-
dc.description.abstractAggregation of nicotinamide (3-pyridine-carboxamide; NA) and picolinamide (2-pyridine-carboxamide; PA) has been investigated by matrix-isolation, supersonic jet and neat solid state infrared spectroscopy, complemented by DFT(B3LYP)/6-311++G(d,p) calculations. For both compounds, the most stable dimeric structure was shown to be the centrosymmetric dimer where two monomers in their most stable forms establish two NHOC hydrogen bonds. The most stable structures of monomers of NA and PA were characterized in detail experimentally by matrix-isolation spectroscopy and theoretically (at both the DFT(B3LYP)/6-311++G(d,p) and MP2/6-311++G(d,p) levels). For nicotinamide, two conformers were found in the matrices, with ca. 80% of the total population adopting the E form. The monomers and dimers of PA and NA were also investigated by infrared spectroscopy of the studied compounds seeded in supersonic jet expansions. These studies revealed that the constraints on the vibrational dynamics in the PA dimer are different from those in the NA dimer. In the PA dimer, the vibrational energy flow out of the N–H stretching mode was shown to be accelerated substantially by the presence of a secondary intramolecular hydrogen bond. In the glassy state of both compounds, the centrosymmetric dimer seems to be the prevalent structure. In the neat crystalline state (KBr pellet), picolinamide keeps this type of dimeric structure as the constituting unit, whereas nicotinamide molecules assume a different arrangement where one of the NHOC bonds is replaced by an NHN(ring) bond. The different crystallograpic structures which were formed by the compounds are reflected in the vibrational spectra of the solids. These observations are correlated with the molecular properties of NA and PA, in particular with the greater conformational mobility of NA compared with PA. This is ascribable to the absence in the NA molecule of the intramolecular NHN(ring) interaction, which exists in PApor
dc.language.isoengpor
dc.publisherRoyal Society of Chemistrypor
dc.rightsopenAccesspor
dc.titleDimer formation in nicotinamide and picolinamide in the gas and condensed phases probed by infrared spectroscopypor
dc.typearticlepor
degois.publication.firstPage7010por
degois.publication.lastPage7021por
degois.publication.titlePhys. Chem. Chem. Physpor
dc.peerreviewedYespor
dc.identifier.doi10.1039/B810002K-
degois.publication.volume10por
item.fulltextCom Texto completo-
item.grantfulltextopen-
item.languageiso639-1en-
crisitem.author.deptFaculdade de Ciências e Tecnologia, Universidade de Coimbra-
crisitem.author.parentdeptUniversidade de Coimbra-
crisitem.author.researchunitCoimbra Chemistry Center-
crisitem.author.orcid0000-0002-8264-6854-
Appears in Collections:FCTUC Química - Artigos em Revistas Internacionais
Files in This Item:
File Description SizeFormat
PCCP, 10 (2008) 7010.pdf793.45 kBAdobe PDFView/Open
Show simple item record

SCOPUSTM   
Citations

27
checked on Nov 8, 2019

WEB OF SCIENCETM
Citations

26
checked on Nov 7, 2019

Page view(s)

110
checked on Nov 12, 2019

Download(s) 20

683
checked on Nov 12, 2019

Google ScholarTM

Check

Altmetric

Dimensions


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.