| Citation | A prolific author and recent (92-96) President of the British Crystallographic Association, Judith Howard is distinguished for her significant contributions to structural chemistry and the pioneering development of low temperature X-ray and neutron diffraction studies of the chemical bond in organic, organometallic and inorganic compounds. Her early work included the structural characterisation of novel pentalene, carbyne and isocyanide complexes, platinum (0) synthons, and key heavy metal hydrides, exploiting methods she devised for the joint refinement of X-ray and neutron data. Recently she has designed and constructed the first ultra low temperature (10K) X-ray diffractometer with a rotating anode source allowing high resolution data collection for precise electron density determination. She is using it not only to probe in detail the bonding in molecular organic and coordination compounds, but also to explore structural, electronic and phase transitions in electrically and magnetically interesting compounds and materials. Examples have included calculation of electrostatic properties such as solid state enhanced dipole moments from charge density analyses (10K), documenting the structural changes responsible for the spin crossover in dichromium triple decker cations (12K), and structurally monitoring for the first time the antiferromagnetic ¨Æ weak ferromagnetic transitions (36K) of a dithiadiazolyl radical, a 'metallic' material containing no metallic elements. |