Themed collection In memory of Professor Ugo Mazzucato (1929–2017)

This issue of Photochemistry & Photobiological Sciences is dedicated to the memory of Professor Ugo Mazzucato, who passed away on 15^th October 2017.

Among stimulus-responsive molecular ring-on-thread rotaxanes and pseudorotaxanes, variants incorporating photochromic sub-units are attracting considerable attention as their properties and structure can be remotely and precisely controlled, additionally without producing chemical waste.

Our study describes how organic photochemists can modify the outcome of a reaction by tuning the wavelength.

Best molecular pair packing geometries for singlet fission in 1,3-diphenylisobenzofuran are predicted.

A molecular motor potentially performing a continuous unidirectional rotation is studied by a multidisciplinary approach including organic synthesis, transient spectroscopy and excited state trajectory calculations.

VUV-irradiation of aqueous solutions containing, both, hydroxylamine (NH₂OH/NH₃OH⁺) and phenol results in the mineralization of the organic substrate and the quantitative reduction of NH₃OH⁺ to NH₄⁺ ions.

cis,trans-1,2-Dideuterio-1,4-diphenyl-1,3-butadiene (ct-DPB_d2) was synthesized and its cis–trans photoisomerization in cyclohexane-d₁₂ (C₆D₁₂) at room temperature was monitored by ¹H NMR spectroscopy.

Fabrics obtained from cellulose spinning were coated with TiO₂ film, through the low pressure plasma sputtering technique, in order to get antibacterial activity.

Shape-persistent azobenzene tetramers functionalized at the periphery with alkyloxy substituents of different lengths have been synthesized and their photochemical behaviour has been investigated.

Small PEGylated silica nanoparticles are synthesized in the presence of high concentrations of organic solvents. This method allows for the efficient incorporation of dyes with poor solubility in water, yielding bright silica nanoparticles.

Advantages and limitations of WO₃/BiVO₄ heterojunctions applied to the photoelectrochemical treatment of some environmental Contaminants of Emerging Concern (CEC).

Adiabatic photoisomerization from ¹Z* to ¹E* has been experimentally evidenced for several styrylarenes. Its weight on the overall cis–trans photoisomerization has been found to increase upon increasing the chromophore size.

Intra- vs. intermolecular hydrogen-bond formation and ESIPT in a bioactive flavonoid result in different emission properties and provide a clue for recognizing its binding to target proteins.

The [2+2] photocycloaddition between two molecules of (E)-2-(3,4-dimethoxystyryl)-quinoxaline (1) in an acetonitrile solution is the first example of the regioselective and stereospecific formation of a cyclobutane derivative without applying any method for the preorganization of molecules in a dilute solution.

UV-induced photooxidation of a 2-substituted indole derivative provides an efficient way for the formation of a benzoxazinone derivative.

The cytotoxic activity of fluphenazine (FPZ) in combination with UVA light was evaluated on three human tumor cell lines, HeLa, MSTO-211H and A431.

A calix[4]arene-based micellar nanoscaffold allows the co-encapsulation of a photolabile fluoroquinolone drug and a poorly photoreactive NO photodonor, simultaneously overcoming the main limitations of the free individual guests such as photolability and low photoreactivity.

The spin state of a nitroxide-labelled anthraquinone can be switched by visible light and modulated by DNA.

A theoretical study allows the modification of a previously assigned structure and justify the high stereoselectivity of the reaction.

The effect of acceptors of varying strengths on the 1P and 2P properties of DAD thiophene based dyes is determined by a combination of experimental and computational methods.

Early events in a water oxidation chromophore-catalyst species are studied; ultrafast energy transfer occurs from the chromophore to the catalytic unit.

A robust dipyrrolylethene derivative which undergoes thermally reversible and fatigue resistant photochromic reactions with appropriate fading rates has been designed and synthesized.