We present the strategic design and synthesis of Os(II) complexes bearing a single pyridyl azolate pi-chromophore with an aim to attain high efficiency blue phosphorescence by way of localized transition. It turns out that our proposal of localized excitation seems to work well upon anchoring a single pi-chromophore on the Os(II) complexes such that the control of MLCT versus pipi* (or even LLC...

New square-planar platinum(II) complexes of the type trans-[Pt(PEt3)2(Tx)(X)] (X = Br, Cl, I or CN) bearing a σ-bonded thioxanthon-2-yl (Tx) ligand have been prepared and characterised by X-ray crystallography, cyclic voltammetry, and by NMR and electronic absorption and luminescence spectroscopy. The ligand X hardly influences the electronic transitions, which indicates that the relevant molec...

The applicability of derivative variable-angle synchronous scanning (DVASS) microemulsion phosphorimetry at room temperature (ME-RTP) was demonstrated for the simultaneous determination of the plant growth regulators 2-naphthoxyacetic acid and 1-naphthalenacetamide in soil samples. This technique permits linear or non-linear paths to be scanned at preselected angles through the excitation–emiss...

The phototropins are blue-light receptors that base their light-dependent action on the reversible formation of a covalent bond between a flavin mononucleotide (FMN) cofactor and a conserved cysteine in light, oxygen or voltage (LOV) domains. The primary reactions of the Avena sativa phototropin 1 LOV2 domain were investigated by means of time-resolved and low-temperature fluorescence spectrosc...

We present a combined experimental and theoretical study on the radiative lifetime of CO in the a (3)Pi(1,2), v=0 state. CO molecules in a beam are prepared in selected rotational levels of this metastable state, Stark-decelerated, and electrostatically trapped. From the phosphorescence decay in the trap, the radiative lifetime is measured to be 2.63+/-0.03 ms for the a (3)Pi(1), v=0, J=1 level...

The effect of different rates of boron incorporation during the growth in diamond on the thermoluminescence (TL) features of this material is investigated. TL studies performed between liquid nitrogen temperature (LNT) and 320 K show some phosphorescence and two other peaks at 226 and 266 K. For the first time, boron level in polycrystalline diamond films was identified by TL by an intense glow...

The effect of humic acid (HA) aggregate formation on the photosensitized generation and subsequent quenching of singlet molecular oxygen O(2)(a(1)Δ(g)) was investigated. Time-resolved O(2)(a(1)Δ(g)) phosphorescence traces were obtained from (a) bulk samples of HA dispersions and (b) microscope-based experiments performed upon irradiation of a single HA aggregate. In the bulk experiments, the de...

The characteristics of tryptophan phosphorescence from the NAD(H)-binding component (dI) component of Rhodospirillum rubrum transhydrogenase are described. This enzyme couples hydride transfer between NAD(H) and NADP(H) to proton translocation across a membrane and is only active as a dimer. Tryptophan phosphorescence spectroscopy is a sensitive technique for the detection of protein conformati...

Recent development of two-photon phosphorescence lifetime microscopy (2PLM) of oxygen enabled first noninvasive high-resolution measurements of tissue oxygenation in vivo in 3D, providing valuable physiological information. The so far developed two-photon-enhanced phosphorescent probes comprise antenna-core constructs, in which two-photon absorbing chromophores (antenna) capture and channel exc...