Crystal structure of vanadyl phthalocyanine, phase II

Abstract

The crystal structure of the title compound has been determined from three-dimensional X-ray diffractometer data. Crystalsare triclinic, space group P i , with Z = 2 in a unit cell of dimensions a = 12.027(6), b = 12.571 (8), c = 8.690(5) A, a = 96.04(5), p = 94.80(5), and y = 68.20(5)". The structure was solved by direct and Fourier methods and refined by least-squares techniques to R (on F ) = 0.062 for 3 042 independent reflections having Fo2 > 30(FO2). The compound [VO(pc)] is molecular with point-group symmetry CI and is non-planar with all pc atoms below the isoindole nitrogen-atom plane. Vanadium has a five-co-ordinate square-pyramidal geometry and is 0.575(1) A above the plane. The V-0 distance is 1.580(3) A; the mean V-N distance is 2.026(7) 8. The compound is composed of sheets of approximately parallel and overlapping [VO(pc)] molecules. Intermolecular contacts occur with three nearest neighbours. shortest centroid-centroid distance is 5.378 A. * The value in parentheses of chemically equivalent distances and angles is the estimated variance of the mean calculated as [ C ( X -.i;)"ln(n -1)y.

A photoelectron diffraction investigation of vanadyl phthalocyanine on Au(111)

“…In the present study the small data set leads to a relatively large value of varR min of 0.08. On this basis the V-O distance is 1.600.04 Å, clearly consistent with the value in bulk crystalline VOPc of 1.580±0.003 Å [9]; the relatively low precision of our value reflects the small data set. The precision in locating the innermost N and C atoms is, of course, significantly worse.…”

“…3 shows a comparison of the averaged experimental O 1s PhD spectrum ( Å. This compares with a value in the crystalline phase of VOPc of 1.580±0.003 Å [9].…”

“…Nevertheless, the variation of the R-factor with the structural parameters determining the position of these atoms shows multiple minima, so to locate the physically meaningful solutions constraints were applied to the local interatomic bondlengths. Specifically, the V-N and N-C nearest-neighbour distances were initially constrained to lie within 0.1 Å of their values in crystalline VOPc [9]) while the C-C bonds were fixed to within ~0. A key question that needs to be answered to validate this discussion concerns the precision with which these atomic positions can be determined relative to the O and V emitter atoms.…”

“…Most MPcs contain a single metal atom at the centre of the molecule, but in VOPc the V-O axis lies perpendicular to the plane of the molecule, leading the vanadyl oxygen atom to 'stick out' of the overall molecular plane. A model of the structure of this molecule, as determined in its crystalline form [9], is shown in Fig. 1; note that while the O atom lies significantly out of the plane defined by the surrounding atoms, and the Sn atom is found to lie closest to the Ag surface in most adsorption phases; i.e.…”

A new form of hydroxyaluminum phthalocyanine by acid treatment. Characterization and photoactivity

“…Different dimeric structures are possible, with two PC macrocycle planes parallel and the Al-OH oriented in the same direction (head-to-tail) or in the opposite direction (head-to-head or tail-to-tail). Similar results were observed for trivalent metal Pc's (21,(33)(34)(35)(36). Thus, the X-ray structure determinations of single crystals of several vacuum-deposited thin film Pc's that have a trivalent or tetravalent metal at centre (e.g.…”