The effect of roughness and thickness of alumina layers, mimicking the passivation layer commonly used in dye‐sensitized photoelectrodes, on the molecular adsorption of P1 dye, 4‐(bi(4‐(2,2‐dicyano‐vinyl)‐thiophene‐2‐yl]‐phenyl]‐aminobenzoic acid) has been studied using surface‐sensitive vibrational sum frequency generation(VSFG) spectroscopy. The VSFG spectra reveal the formation of poorly ordered dye layers on relatively rough surfaces where XPS measures a higher dye loading. Furthermore, these poorly ordered dye molecules are responsible for the generation of trapped electronic states as probed by successive photoluminescence (PL) measurements. Surface sensitive VSFG spectroscopy in combination with XPS and PL measurements provide complementary spectral information on ordering of the adsorbed dyes, their density on the surface and electronic states of the adsorbed monolayer which are prerequisite for improving our understanding of molecularly functionalized photoelectrodes and their further development.

The reaction of MCl4(thf)2 (M = Zr, Hf) with 1,4‐dilitiobutane in diethyl ether at –25 °C or at 0 °C with a molar ratio of 1 : 3 yields the homoleptic “ate” complexes [(thf)4Li] [{(thf)Li}M(C4H8)3] 1‐Zr (M = Zr) and 1‐Hf (M = Hf). The crystalline compounds form ion lattices with solvent‐separated [(thf)4Li]+ cations and [{(thf)Li}M(C4H8)3]– anions. The NMR spectra at –20 °C show magnetic equivalence of the M–CH2 and of the β‐CH2 groups of the butane‐1,4‐diide ligands on the NMR time scale. Analogous reactions of MCl4(thf)2 with 1,4‐dilithiobutane with a molar ratio of 1 : 2 proceed unclear. However, single crystals of [Li(thf)4] [HfCl5(thf)] (2) can be isolated with the hafnium atom in a distorted octahedral coordination sphere of five chloro and one thf ligand. NMR spectra allow to elucidate the time‐dependent degradation of 1‐Hf and 1‐Zr in THF and toluene at 25 °C via THF cleavage. Addition of tmeda to a solution of 1‐Zr allows the isolation of intermediately formed [{(tmeda)Li}2Zr(nBu)2(C4H8)2] (3).

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