Electronic spectra over the 50 000-20 000-cm-1 region are reported for well-characterized chromophores having Cu(ll)-imidazole (ImH) and Cu(Il)-imidazolate (Im_) units. For tetragonal Cu(Il)-lmH chromophores, three ligand to metal charge-transfer (LMCT) absorptions originate from the -symmetry nitrogen donor lone pair and from two -symmetry ring orbitals, one having primarily carbon character ( ) and the other having primarily nitrogen character (7 2). These ff(lmH) 2( ) -and TTi(lmH) ->• Cu(Il) LMCT absorptions occur at ~220, ~260, and ~330 nm, respectively. Ligand rotation causes the -symmetry absorptions to be broadened for solutions containing geometrically unconstrained Cu(ll)-ImH complexes. The -symmetry absorptions generally are well-resolved spectral features of crystalline complexes, and may be split when the ImH groups have nonequivalent orientations. The cr(ImH) -Cu(II) absorption at 220 nm is insensitive to ligand rotation about the Cu-N axis, and is well resolved from the ligand-localized absorption at ~205 nm. The Cu(l l)-lm" complexes exhibit an additional and characteristic broad absorption at --375 nm for which a tentative assignment has been suggested. Tetragonal type 2 and type 3 copper protein chromophores are expected to exhibit corresponding ( ) -* Cu(ll) LMCT transitions in the near-UV region. Such absorptions are expected to be red shifted for the approximately tetrahedral type 1 copper chromophores. The reported spectra of the above types of proteins briefly are reconsidered from this point of view.

The International Centre for Diffraction Data (ICDD) produces the Powder Diffraction File (PDF). This paper discusses some of the seminal events in the history of producing this primary reference for powder diffraction. Recent key events that center on collaborative initiatives have led to an enormous jump in entry population for the PDF. Collective efforts to editorialize the PDF are ongoing and provide enormous added value to the file. Recently, the ICDD has created a new series of the PDF, designated PDF-4. These relational database structures are being used to house the PDF of the future. The design and benefits of the PDF-4 are described.

The International Centre for Diffraction Data (ICDD) is responding to the changing needs in powder diffraction and materials analysis by developing the Powder Diffraction File (PDF) in a very flexible relational database (RDB) format. The PDF now contains 136,895 powder diffraction patterns. In this paper, an attempt is made to give an overview of the PDF-4, search/match methods and the advantages of having the PDF-4 in RDB format. Some case studies have been carried out to search for crystallization trends, properties, frequencies of space groups and prototype structures. These studies give a good understanding of the basic structural aspects of classes of compounds present in the database. The present paper also reports data-mining techniques and demonstrates the power of a relational database over the traditional (flat-file) database structures.

Commercial atomoxetine hydrochloride crystallizes in the orthorhombic space group P2 1 2 1 2 1 (#19), with a = 7.362 554(12), b = 13.340 168 (27), c = 16.701 887(33) Å, V = 1640.421(5) Å 3 , and Z = 4. The structure was solved and refined using synchrotron powder diffraction data, and Rietveld and density functional techniques. The most prominent feature of the structure is zigzag chains of N-H···Cl hydrogen bonds along the a-axis. The powder pattern has been submitted to the ICDD for inclusion in future releases of the Powder Diffraction File™.

The title complex, Cu ( [9]aneN3)C12 (l), behaves anomalously with regard to the well-known macrocyclic effect. Typically, macrocyclic pol amine Cu(I1) complexes exhibit polyamines.2 However, the formation constant of 1 (log K is: 16) is smaller than that of Cu(dien)z+ (log K = 18.0).*g3 larger formation constants yh t an those of corresponding linear dien 19 lane% In contrast, formation constants of Ni( [9]aneN#+ and Zn-([9]a11eN~)~' (log K = 16.2 and 11.6, respectively) are substantially larger than those of Ni(dien)2+ and Zn(dien)" (log K = 10.7 and 8.9, re~pectively).~ The anomalous behavior of 1 has been attributed2" to steric requirements of Cu(I1) which have been frustrated in part by structural constraints of the [9]aneN3 ligand. The present study was undertaken to help understand these constraint^.^ Experimental SectionPreparation of 1. 1,4,7-Triazacyclononane trihydrochloride ( [9]aneN3.3HC1) was prepared by appropriate modification of a published procedure for 1,5,9,13-tetraazacy~lohexadecane.~ Evaporation of a solution of [9]aneN3.3HC1 (5 mmol, 1.24 g), CuC12 (5 mmol, 0.85 g), and 15 mL of 1 N sodium hydroxide yielded sodium chloride crystals and large blue plates of 1 which were separated manually and recrystallized from water to yield pure 1.