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Fast assembly of fock matrices utilising symmetry properties of the basis set (1973)
Journal Article
Brailsford, D. F., & Hylton, J. (1973). Fast assembly of fock matrices utilising symmetry properties of the basis set. Chemical Physics Letters, 18(4),

A method of assembling the elements of the Fock matrix is described which is a modification of that due to Dacre. Lists of symmetry equivalent one-electron integrals are used as pointers to abbreviate the process of collecting two-electron integrals... Read More about Fast assembly of fock matrices utilising symmetry properties of the basis set.

3-body energy terms in a quartet state of H3 (1971)
Journal Article
Brailsford, D. F., & Ford, B. (1971). 3-body energy terms in a quartet state of H3. Chemical Physics Letters, 12(1),

Calculations of the 3-body energy term in a quartet (4A2 ) state of H3 (equilateral triangle nuclear-configurations) show a minimum in the 3-body energy for a side length of about 1.3 bohrs.

Symmetry properties of one- and two- electron molecular integrals (1971)
Journal Article
Brailsford, D. F., & Hall, G. G. (1971). Symmetry properties of one- and two- electron molecular integrals. International Journal of Quantum Chemistry, V,

The maximum numbers of distinct one- and two-electron integrals that arise in calculating the electronic energy of a molecule are discussed. It is shown that these may be calculated easily using the character table of the symmetry group of the set of... Read More about Symmetry properties of one- and two- electron molecular integrals.

Electric field strengths and ion trajectories in sharp-edge field ionization sources (1970)
Journal Article
Brailsford, D. F. (1970). Electric field strengths and ion trajectories in sharp-edge field ionization sources. Journal of Physics D: Applied Physics, 3,

On the presumption that a sharp edge may be represented by a hyperbola, a conformal transformation method is used to derive electric field equations for a sharp edge suspended above a flat plate. A further transformation is then introduced to give el... Read More about Electric field strengths and ion trajectories in sharp-edge field ionization sources.

Calculated ionization potentials of the linear alkanes (1970)
Journal Article
Brailsford, D. F., & Ford, B. (1970). Calculated ionization potentials of the linear alkanes. Molecular Physics, 18(5),

The equivalent orbital (EO) method is investigated and used for predicting outer and inner ionization potentials of the linear alkanes. The calculated ionization potentials are in good agreement with those observed in photoelectron spectra provided t... Read More about Calculated ionization potentials of the linear alkanes.

Calculation of electric field strengths at a sharp edge (1968)
Journal Article
Brailsford, D. F., & Robertson, A. J. B. (1968). Calculation of electric field strengths at a sharp edge

Sharp edges were first used for field ionisation mass spectrometry by Beckey. Although Cross and Robertson found that etched metal foils were more effective than razor blades for field ionisation, blades are very convenient for determination of field... Read More about Calculation of electric field strengths at a sharp edge.

Structural optimization of molecular clusters with density functional theory combined with basin hopping
Journal Article
Do, H., & Besley, N. A. Structural optimization of molecular clusters with density functional theory combined with basin hopping. Journal of Chemical Physics, 137(13), Article 134106. https://doi.org/10.1063/1.4755994

Identifying the energy minima of molecular clusters is a challenging problem. Traditionally, search algorithms such as simulated annealing, genetic algorithms, or basin hopping are usually used in conjunction with empirical force fields. We have impl... Read More about Structural optimization of molecular clusters with density functional theory combined with basin hopping.

Measuring proton shift tensors with ultrafast MAS NMR
Journal Article
Miah, H. K., Bennett, D. A., Iuga, D., & Titman, J. J. Measuring proton shift tensors with ultrafast MAS NMR. Journal of Magnetic Resonance, 235, https://doi.org/10.1016/j.jmr.2013.07.005

A new proton anisotropic-isotropic shift correlation experiment is described which operates with ultrafast MAS, resulting in good resolution of isotropic proton shifts in the detection dimension. The new experiment makes use of a recoupling sequence... Read More about Measuring proton shift tensors with ultrafast MAS NMR.

A generic ?* shape resonance observed in energy-dependent photoelectron angular distributions from two-colour, resonant multiphoton ionization of difluorobenzene isomers
Journal Article
Staniforth, M., Daly, S., Reid, K. L., & Powis, I. A generic ?* shape resonance observed in energy-dependent photoelectron angular distributions from two-colour, resonant multiphoton ionization of difluorobenzene isomers. Journal of Chemical Physics, 139(6), Article 064304. https://doi.org/10.1063/1.4817324

We present new evidence for the existence of a near threshold ?* shape resonance as a common feature in the photoionization of each isomer of difluorobenzene. Experimentally this is revealed by significant changes in the anisotropy of the photoelectr... Read More about A generic ?* shape resonance observed in energy-dependent photoelectron angular distributions from two-colour, resonant multiphoton ionization of difluorobenzene isomers.