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Augmented reality (AR) has the potential to reshape the mobile shopping experience and create more meaningful consumer-brand relationships. Yet, the broader experiential and brandrelated impact of AR remains unclear, as much existing research adopts an app-centric perspective centered on consumers' motivations for and reactions to using AR applications. The current article takes a more holistic approach to examine what consumer-brand relationships can be facilitated through augmented reality. Through an ethnographic study of Sephora's mobile AR shopping app, we find that a close and intimate (rather than transactional) relationship can emerge due to how the branded AR app is incorporated into consumers' intimate space and their sense of self. This study thus broadens the focus of AR research from the immediate physical context into which virtual information is embedded, to the wider spatial-symbolic context of where consumers use AR apps, as well as to the inner context of how self-augmentations are integrated into consumers' self-concepts.

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Astronomical observations indicate that formation and destruction of dust mantles on cometary nuclei may be the cause for erratic and systematic variations of eometary activity, i.e. emission of dust. A laboratory experiment (KOSI-9) has been performed Io study the evolution of a dust mantle on top of a sublimating ice-dust mixture in vacuum. A sample consisting of water ice with a 10% (by weight) admixture of olivine grains has been insolated in three periods at variable intensities from 200 to 1900 W/m 2. Both increasing surface temperature of the sample and decreasing gas and particle emissions indicated the formation of a dust mantle during the first period. During the second insolation period after the gas flux had reached a critical value of a few 1021 water molecules m -2 s -1, avalanches of mantle material occurred on the inclined sample surface, broke up the mantle locally, and opened up a fresh icy surface. Enhanced ice and dust particle emission resumed for some time from these spots. A large number of the emitted dust particles were of a fluffy aggregate structure, i.e., they had large cross section to mass ratios compared to compact particles. During the third period the critical gas flux was not reached and no enhanced dust and ice emission was observed. A dry dust mantle of a few millimeters thickness developed during the course of the experiment. Consequences of these findings for eometary scenarios are discussed.

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The novel dark green or violet and air-sensitive 1-aza-1,3-diene titanocene complexes Cp2Ti[N(R1)CHC(R2)CH(Ph)] [R1 = t-Bu, R2 = H (7a); R1 = C6H4-4-Me, R2 = H (7b); R1 = c-C6H11, R2 = Me (7c)] were prepared by the complexation of the 1-aza-1,3-dienes 1a−c to the titanocene “Cp2Ti” generated in situ by reduction of Cp2TiCl2 with magnesium. The solid-state structure of 7c shows a bent azatitanacyclic ring with a fold angle of 130.9(4)°. A series of electron-deficient 14e 1-aza-1,3-diene titanium complexes CpTi[N(R1)CHC(Me)CH(Ph)]Cl [R1 = c-C6H11 (8a), t-Bu (8b), C6H4-2-Me (8c), C6H4-4-Me (8d)] has also been prepared by reduction of CpTiCl3 with magnesium in the presence of the 1-aza-1,3-dienes R1NCHC(Me)CH(Ph) 1c−f. These new complexes were isolated as air-sensitive brown (8a,b) or dark red (8c,d) crystals in 50−65% yield. The X-ray crystal structure of 8c revealed that the coordination geometry for the 1-aza-1,3-diene ligands has substantial σ2,π-η4-metallacyclopent-4-ene character. The 1-aza-1,3-diene complexes 8a,c,d only exhibit supine geometry as confirmed by 1H NMR spectroscopy, while 8b exists in both the conventional supine geometry and the prone geometry, which is demonstrated by quite different 1H NMR chemical shift values. Addition of 8c to 1 equiv of acetophenone gives the seven-membered metallacyclic ring system CpTi[N(C6H4-4-Me)CHC(Me)CH(Ph)C(Me)PhO] (9), whose structure has also been characterized by NMR spectral data and by X-ray diffraction analysis. In contrast to 8c, the 1-aza-1,3-diene titanocene complex Cp2Ti[N(c-C6H11)CHC(Me)CH(Ph)] (7c) does not react with acetophenone even at high temperatures.

The reduction of CpzZrClz in THF by Mg in the presence of l-aza-1,3-dienes 2ad generates the orange air-sensitive zirconocene(s-cis-l-aza-1,3-diene) complexes 3ad. 'H-and I3C-NMR spectral data of 3ad indicate that the bonding of the heterodiene ligand has 02,x-metallacyclopentene rather than q4-l-aza-1,3-diene character. No evidence for s-trans-heterodiene coordination was found in any of the new zirconocene complexes. The molecular structure of 3d has been deter-mined by single-crystal X-ray diffraction, confirming the envelope-shaped 02,x-type structure also in the solid state. 3b slowly reacts with one molar equivalent of acetophenone to give a seven-membered oxaazametallacycle Cp,Zr(NRCH = CHCHPhC(Me)PhO) (4) which has a cis-C = C bond in the ring. The structure of 4 has been determined by NMR and X-ray diffraction.

Dinuclear platina-β-diketones [Pt2{(COR)2H}2(μ-Cl)2] (R = Me (1a), Et (1b)) react with phosphines (PPh3, Ph2P(CH2) n PPh2, n = 1−3) and triphenylarsine to form acylplatinum(II) complexes as well as acetaldehyde and propionaldehyde, respectively. Reaction of 1 with 4 equiv of PPh3 and AsPh3 leads to trans-[PtCl(COR)L2] (L = PPh3 (4), AsPh3 (5); R = Me (a), Et (b)). Reaction of 1a with PPh3 in a 1:2 molar ratio results in formation of carbonyl(methyl)platinum complexes [PtCl(Me)(CO)(PPh3)] (11). Cationic A-frame complexes [Pt2(COR)2(μ-Cl)(μ-dppm)2]Cl (R = Me (6a), Et (6b)) were formed in reactions of 1 with 2 equiv of Ph2PCH2PPh2 (dppm). Treatment of 1a with Ph2P(CH2)2PPh2 (dppe) and Ph2P(CH2)3PPh2 (dppp) yields complexes [PtCl(COMe){Ph2P(CH2) n PPh2}] (n = 2 (7), 3 (8)). However, at low temperatures (−30 °C) reactions of 1a with dppe and dppp afford mononuclear cationic platina-β-diketones [Pt{(COMe)2H}(Ph2P(CH2) n PPh2)]Cl (n = 2 (9a), 3 (10)). The reaction of [Pt2{(COMe)2H}2(μ-Cl)2] (1a) with pyridine (py) or quinoline (quin) results in cleavage of the Pt−Cl−Pt bridges, yielding mononuclear neutral platina-β-diketones [PtCl{(COMe)2H}L] (L = py (13a), quin (13b)). In the solid state complex 13b reveals a nonplanar arrangement of the platina-β-diketone unit with a strong hydrogen bond (O···O 2.419(8) Å). From all these findings the mechanism of the aldehyde formation in the reactions of platina-β-diketones 1 with L (PPh3, AsPh3) and LL (dppm, dppe, dppp) is deduced.