The Discovery of New Galaxy Members in the NGC 5044 and NGC 1052 Groups

We present the results of neutral hydrogen (HI) observations of the NGC 5044 and NGC 1052 groups, as part of a GEMS (Group Evolution Multiwavelength Study) investigation into the formation and evolution of galaxies in nearby groups. Two new group members have been discovered during a wide-field HI imaging survey conducted using the ATNF Parkes telescope. These results, as well as those from followup HI synthesis and optical imaging, are presented here. J1320-1427, a new member of the NGC 5044 Group, has an HI mass of M_HI=1.05e9Msun and M_HI/L_B=1.65 Msun/Lsun, with a radial velocity of v=2750km/s. The optical galaxy is characterised by two regions of star formation, surrounded by an extended, diffuse halo. J0249-0806, the new member of the NGC 1052 Group, has M_HI=5.4e8Msun, M_HI/L_R=1.13 Msun/Lsun and v=1450km/s. The optical image reveals a low surface brightness galaxy. We interpret both of these galaxies as irregular type, with J0249-0806 possibly undergoing first infall into the NGC 1052 group.Comment: Accepted for publication in MNRAS. 21 pages, 13 figures. Also available with high-resolution figures at http://www.astro.livjm.ac.uk/~npfm/Papers/mmb04.ps.g

Structural and spectroscopic studies of some copper(I) halide tert-butyl isocyanide adducts

Single-crystal structural characterizations confirm the existence of the unusual 1 : 4 copper(I) halide : unidentate ligand adducts [Cu(CNt-Bu)(4)]X for X = Cl, Br (two forms), I (the chloride and one form of the bromide being solvated) with crystal packing dominated by stacks of interleaving cations. Cu-C range between 1.941(2) and 1.972(4) angstrom. The structure of the 1 : 2 chloride complex is also recorded, being [ClCu(CNt-BU)(2)], with the copper(I) atom environment trigonal planar, while CuCN: (CNt-Bu) (1 : 1) is a single-stranded polymer which spirals about a crystallographic 3-axis (CN scrambled), the ligands being pendant from the ...CuCNCuCN... string. The Cu-65 static broadline NMR spectra of [Cu(CNt-BU)(4)]I and [Cu(CNt-Bu)(4)]Br center dot H2O in the solid state exhibit dominant, narrow -1/2 +1/2 central transition resonances and associated +/- 1/2 +/- 3/2 satellite transition resonances which are characteristic of first-order quadrupole broadened systems, while associated high-resolution Cu-65 MAS NMR data provide accurate measurement of the (CU)-C-65 isotropic chemical shifts. Both approaches provide complete data on the quadrupole and chemical shift interactions which contribute to these spectra. Far-IR spectra of products of reactions involving a range of CuX : t-BuNC ratios reveal the existence of 1 : 1.5 adducts for X = Br, I. Metal-carbon and metal-halogen bands are assigned in the far-IR spectra, which indicate a binuclear double halogen-bridged structure for the 1 : 1.5 complexes