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The crystalline structure of the phenazine overlayer physisorbed on a graphite surface
The monolayer crystal structure of phenazine adsorbed on graphite is determined by a combination of synchrotron X-ray diffraction and DFT calculations. The molecules adopt a rectangular unit cell with lattice parameters a = 13.55 Ă
and b = 10.55 Ă
, which contains 2 molecules. The plane group of the unit cell is p2gg, and each molecule is essentially flat to the plane of the surface, with only a small amount of out-of-plane tilt. Density Functional Theory (DFT) calculations find a minimum energy structure with a unit cell which agrees within 7.5% with that deduced by diffraction. DFT including dispersion force corrections (DFT+D) calculations help to identify the nature of the intermolecular bonding. The overlayer interactions are principally van der Waals, with a smaller contribution from weak C-Hâ˘â˘â˘N hydrogen bonds. This behaviour is compared with that of 4,4â-bipyridyl.We acknowledge financial support for AB from an EPSRC DTA award from the Department of Chemistry, University of Cambridge; and BP for financial support for CT. We thank Diamond Light Source for access to beamline I11 (EE7761) that contributed to the results presented here. The DFT calculations were performed using the Darwin Supercomputer of the University of Cambridge High Performance Computing Service.This is the accepted manuscript. The final version is available from Taylor & Francis at http://www.tandfonline.com/doi/abs/10.1080/00268976.2013.793844#.VGHd34XziEo
Patterns and outcomes of preterm hospital admissions during pregnancy in NSW, 2001-2008
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Supramolecular self-assembled network formation containing N¡¡¡Br halogen bonds in physisorbed overlayers.
The formation of a halogen bonded self-assembled co-crystal physisorbed monolayer containing N¡¡¡Br interactions is reported for the first time. The co-crystal monolayer is identified experimentally by synchrotron X-ray diffraction and the structure determined. Density functional theory (DFT) calculations are also employed to assess the magnitudes of the different interactions in the layer. Significantly, compared to other halogen bonds in physisorbed monolayers we have reported recently, the N¡¡¡Br bond here is found to be non-linear. It is proposed that the increasing importance of the lateral hydrogen bond interactions, relative to the halogen bond strength, leads to the bending of the halogen bonds.We acknowledge financial support for AB from EPSRC DTA award from the Department of Chemistry, University of Cambridge. We acknowledge Diamond Light Source for time on beamline I11 under proposals EE6511 and EE7761.This is the final version of the article. It first appeared from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C4CP03379
Race and sex: teachers' views on who gets ahead in schools?
The research reported here was part of a large study of the impact of age, disability, race and sex on the teaching profession in England. The basic question asked in this research was how do these factors interact with career aspirations and achievements of classteachers, promoted teachers and headteachers? There were three different data sources: a large postal survey drawn from diverse geographic regions across England with over 2000 respondents; faceâtoâface individual interviews with over 100 teachers in 18 case study schools from across all of the main regions of England; discussions with special interest groups of teachers. Not surprisingly, the answer to the above question was complex. Nonetheless, the paper's conclusion highlights some of the noteworthy themes across this broad sample of teachers from primary, secondary and special schools
Ogbu and the debate on educational achievement: an exploration of the links between education, migration, identity and belonging
This paper looks at some of the issues raised by Ogbuâs work in relation to the education of different minority ethnic groups. Ogbu poses questions such as the value attached to education,
its links to the future and its measurable outcomes in terms of âsuccessâ as experienced by black participants. The desire for better life chances leads families to consider migration to a new country or resettlement within the same country, thus making migration both a local and a global phenomenon. As an example, attention is drawn to the situation facing South Asian
children and their families in the UK. In terms of ethnicity and belonging, the wider question that is significant for many countries in the West after âNine-Elevenâ is the education of Muslim children. A consideration of this current situation throws Ogbuâs identification of âautonomous minorityâ into question. It is argued that a greater understanding of diverse needs has to be
accompanied by a concerted effort to confront racism and intolerance in schools and in society, thus enabling all communities to make a useful contribution and to avoid the âriskâ of failure and disenchantment
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