Theoretica Chimica Acta A Journal for Structure, Dynamics and Radiation Volume 87 Number 4/5 1994 Inga Fischer-Hjalmars honorary issue B. Roos Introduction 243 A. Henriksson-Enflo, H. Holmgren Metals in biology: Electronic structure, properties and charge transfer for copper complexes of glyoxal and dithiene 247 U. Wahlgren, P. E. M. Siegbahn On the use of small d-spaces in SCF and CI calculations on transition metals 267 P. E. M. Siegbahn The activation of the C-H bond in acetylene by second row transition metal atoms 277 L. G. M. Pettersson The bonding between NO and the NiO(l00)surface 293 C. Ribbing, M. Odelius, J. Kowalewski, L. Pettersson Simple non-empirical calculations of the zero-field splitting in bis(aquo) bis(malonato) nickel(II) 307 P. Schwerdtfeger, J. Li, P. Pyykkoe The polarisability of Hg and the ground-state interaction potential of Hg_2 313 W. Luettke, P. N. Skancke, M. Traetteberg On the dimerization process of nitroso compounds. A theoretical study of the reaction 2 HNO -> (HNO_2) 321 I. Panas Two hypothetical structures of solid FCN 335 S. Knuts, B. F. Minaev, H. Agren, O. Vahtras The phosphorescence of benzene obtained by ab initio and semi- empirical calculations 343 O. Gropen, M. Sjovoll, H. Stromsnes, E. Karlsen, O. Swang, K. Faagri, jr RECP calculations for reactions of H_2 with Pt, Os, Ir, and Re - a systematic comparison 373 L. Serrano-Andres, B. O. Roos, M. Merchan Theoretical study of the electronic spectra of cis-1,3,5- hexatriene and cis-1,3-butadiene 387 M. P. Fuelscher, B. O. Roos The excited states of pyrazine: A basis set study 403 Indexed in Current Contents TCHAAM 87 (4/5) 243-414 January 1994 Printed on acid-free paper Theoretica Chimica Acta A Journal for Structure, Dynamics and Radiation Volume 87 Number 6 1994 B. W. Clare Frontier orbital energies in quantitative stucture-activity relationships: A comparison of quantum chemical methods 415 S.Takane,T.Fueno Electronic structure and the hydrogen-shift isomerization of hydrogen nitryl HNO_2 431 R E. M. Siegbahn The bonding in second row transition metal dihydrides, difluorides and dichlorides 441 S. Don Travlos, J. C. A. Boeyens A new method for approximate solution of one-dimensional Schroedinger equations 453 R L. A. Popelier An analytical expression for interatomic surfaces in the theory of atoms in molecules 465 Book review 477 Announcement 478 Contents of Volume 87 / Subject index Indexed in Current Contents TCHAAM 87 (6) 415-478 February 1994 ------------------------------------------------------------