0000000001301472
AUTHOR
Kamil Lang
showing 24 related works from this author
Tuning the photophysical properties of anti-B18H22: efficient intersystem crossing between excited singlet and triplet states in new 4,4'-(HS)2-anti-…
2013
The tuning of the photophysical properties of the highly fluorescent boron hydride cluster anti-B18H22 (1), by straightforward chemical substitution to produce 4,4'-(HS)2-anti-B18H20 (2), facilitates intersystem crossing from excited singlet states to a triplet manifold. This subsequently enhances O2((1)Δg) singlet oxygen production from a quantum yield of ΦΔ ∼ 0.008 in 1 to 0.59 in 2. This paper describes the synthesis and full structural characterization of the new compound 4,4'-(HS)2-anti-B18H20 (2) and uses UV-vis spectroscopy coupled with density functional theory (DFT) and ab initio computational studies to delineate and explain its photophysical properties.
Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured macropolyhedral boron h…
2018
Reaction of anti-B18H221 with pyridine in neutral solvents gives sparingly soluble B16H18-3',8'-Py23a as the major product (ca. 53%) and B18H20-6',9'-Py22 (ca. 15%) as the minor product, with small quantities of B18H20-8'-Py 4 (ca. 1%) also being formed. The three new compounds 2, 3a and 4 are characterized by single-crystal X-ray diffraction analyses and by multinuclear multiple-resonance NMR spectroscopy. Compound 2 is of ten-vertex nido:ten-vertex arachno two-atoms-in-common architecture, long postulated for a species with borons-only cluster constitution, but previously elusive. Compound 3a is of unprecedented ten-vertex nido:eight-vertex arachno two-atoms-in-common architecture. The si…
Thermochromic Fluorescence from B18H20(NC5H5)2: An Inorganic–Organic Composite Luminescent Compound with an Unusual Molecular Geometry
2017
BH(NCH) is a rare example of two conjoined boron hydride subclusters of nido and arachno geometrical character. At room temperature, solutions of BH(NCH) emit a 690 nm fluorescence. In the solid state, this emission is shifted to 620 nm and intensifies due to restriction of the rotation of the pyridine ligands. In addition, there is a thermochromicity to the fluorescence of BH(NCH). Cooling to 8 K engenders a further shift in the emission wavelength to 585 nm and a twofold increase in intensity. Immobilization in a polystyrene thin-film matrix results in an efficient absorption of pumping excitation energy at 414 nm and a 609 nm photostable fluorescence. Such fluorescence from polystyrene t…
Photochromic System among Boron Hydrides: The Hawthorne Rearrangement
2019
Photoswitchable molecules have attracted wide interest for many applications in chemistry, physics, and materials science. In this work, we revisit the reversible photochemical and thermal rearrangements of the two B20H182– isomers reported by Hawthorne and Pilling in 1966, whose mechanism had not been understood so far. We investigate the rearrangements by means of a joint experimental and computational study with the outcome that B20H182– represents the first boron-based photochromic system ever reported. Both photochemical and thermal isomerizations occur through the same intermediate and involve a diamond–square–diamond (DSD) mechanism. Given the absence within boron chemistry of named …
Distinct Photophysics of the Isomers of B18H22 Explained
2012
The photophysics of the two isomers of octadecaborane(22), anti- and syn-B 18H 22, have been studied by UV-vis spectroscopic techniques and theoretical computational methods. In air-saturated hexane, anti-B 18H 22 shows fluorescence with a high quantum yield, Φ F = 0.97, and singlet oxygen O 2( 1Δ g) production (Φ Δ ∼ 0.008). Conversely, isomer syn-B 18H 22 shows no measurable fluorescence, instead displaying much faster, picosecond nonradiative decay of excited singlet states. Computed potential energy hypersurfaces (PEHs) for both isomers rationalize these data, pointing to a deep S 1 minimum for anti-B 18H 22 and a conical intersection (CI) between its S 0 and S 1 states that lies 0.51 e…
A Series of Ultra-Efficient Blue Borane Fluorophores
2020
13 pags., 14 figs., 5 tabs.
Effect of Iodination on the Photophysics of the Laser Borane anti-B18H22: Generation of Efficient Photosensitizers of Oxygen
2019
Treatment of the laser borane anti-B18H22 (compound 1) with iodine in ethanol gives the monoiodinated derivative 7-I-anti-B18H21 (compound 2) in 67% yield, or, by reaction with iodine or ICl in the presence of AlCl3 in dichloromethane, the diiodinated derivative 4,4'-I2-anti-B18H20 (compound 3) in 85% yield. On excitation with 360 nm light, both compounds 2 and 3 give strong green phosphorescent emissions (λmax = 525 nm, ΦL = 0.41 and λmax = 545 nm, ΦL = 0.71 respectively) that are quenched by dioxygen to produce O2(1Δg) singlet oxygen with quantum yields of ΦΔ = 0.52 and 0.36 respectively. Similarly strong emissions can be stimulated via the nonlinear process of two-photon absorption when …
CCDC 1441506: Experimental Crystal Structure Determination
2018
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Tomáš Jelínek, John D. Kennedy, Ivana Císařová, Robert D. Kennedy, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Kamil Lang, William Clegg|2018|Dalton Trans.|47|1709|doi:10.1039/C7DT03823B
CCDC 2009109: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 2009108: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 1514165: Experimental Crystal Structure Determination
2020
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Luis Cerdán, Kamil Lang, Tomáš Jelínek, Josep M. Oliva, Drahomír Hnyk, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Jiří Martinčík, Martin Nikl, John D. Kennedy|2017|Adv. Opt. Mater.|5|1600694|doi:10.1002/adom.201600694
CCDC 2009112: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 2009113: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 1859436: Experimental Crystal Structure Determination
2019
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Jonathan Bould, Jakub Braborec, Kaplan Kirakci, Kamil Lang, Ivana Císařová, Pavel Kubát, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Lenka Slušná, Eva Noskovičová, Dušan Lorenc|2019|Inorg.Chem.|58|10248|doi:10.1021/acs.inorgchem.9b01358
CCDC 2009110: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 1441507: Experimental Crystal Structure Determination
2018
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Tomáš Jelínek, John D. Kennedy, Ivana Císařová, Robert D. Kennedy, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Kamil Lang, William Clegg|2018|Dalton Trans.|47|1709|doi:10.1039/C7DT03823B
CCDC 2009106: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 2009105: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 2009107: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 1441504: Experimental Crystal Structure Determination
2018
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Tomáš Jelínek, John D. Kennedy, Ivana Císařová, Robert D. Kennedy, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Kamil Lang, William Clegg|2018|Dalton Trans.|47|1709|doi:10.1039/C7DT03823B
CCDC 1859437: Experimental Crystal Structure Determination
2019
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Jonathan Bould, Jakub Braborec, Kaplan Kirakci, Kamil Lang, Ivana Císařová, Pavel Kubát, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Lenka Slušná, Eva Noskovičová, Dušan Lorenc|2019|Inorg.Chem.|58|10248|doi:10.1021/acs.inorgchem.9b01358
CCDC 2009111: Experimental Crystal Structure Determination
2020
Related Article: Jonathan Bould, Kamil Lang, Kaplan Kirakci, Luis Cerdán, Daniel Roca-Sanjuán, Antonio Francés-Monerris, William Clegg, Paul G. Waddell, Marcel Fuciman, Tomáš Polívka, Michael G. S. Londesborough|2020|Inorg.Chem.|59|17058|doi:10.1021/acs.inorgchem.0c02277
CCDC 1441505: Experimental Crystal Structure Determination
2018
Related Article: Michael G. S. Londesborough, Jiří Dolanský, Tomáš Jelínek, John D. Kennedy, Ivana Císařová, Robert D. Kennedy, Daniel Roca-Sanjuán, Antonio Francés-Monerris, Kamil Lang, William Clegg|2018|Dalton Trans.|47|1709|doi:10.1039/C7DT03823B
CCDC 912917: Experimental Crystal Structure Determination
2013
Related Article: Vicenta Saurí, Josep M. Oliva, Drahomír Hnyk, Jonathan Bould, Jakub Braborec, Manuela Merchán, Pavel Kubát, Ivana Císařová, Kamil Lang, and Michael G. S. Londesborough|2013|Inorg.Chem.|52|9266|doi:10.1021/ic4004559