The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Suchada Rajca - One of the best experts on this subject based on the ideXlab platform.
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thermally and magnetically robust Triplet Ground State diradical
Journal of the American Chemical Society, 2019Co-Authors: Nolan M Gallagher, Suchada Rajca, Hui Zhang, Tobias Junghoefer, Erika Giangrisostomi, Ruslan Ovsyannikov, Maren Pink, M B Casu, Andrzej RajcaAbstract:High spin (S = 1) organic diradicals may offer enhanced properties with respect to several emerging technologies, but typically exhibit low singlet Triplet energy gaps and possess limited thermal stability. We report Triplet Ground State diradical 2 with a large singlet–Triplet energy gap, ΔEST ≥ 1.7 kcal mol–1, leading to nearly exclusive population of Triplet Ground State at room temperature, and good thermal stability with onset of decomposition at ∼160 °C under inert atmosphere. Magnetic properties of 2 and the previously prepared diradical 1 are characterized by SQUID magnetometry of polycrystalline powders, in polystyrene glass, and in other matrices. Polycrystalline diradical 2 forms a novel one-dimensional (1D) spin-1 (S = 1) chain of organic radicals with intrachain antiferromagnetic coupling of J′/k = −14 K, which is associated with the N···N and N···O intermolecular contacts. The intrachain antiferromagnetic coupling in 2 is by far strongest among all studied 1D S = 1 chains of organic radicals...
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High-Spin Organic Diradical with Robust Stability
Journal of the American Chemical Society, 2016Co-Authors: Nolan M Gallagher, Suchada Rajca, Maren Pink, Jackson J. Bauer, Andrzej RajcaAbstract:Triplet Ground-State organic molecules are interesting with respect to several emerging technologies but typically exhibit limited stability. We report two organic diradicals, one of which possesses a Triplet Ground State (2J/kB = 234 ± 36 K) and robust stability at elevated temperatures. We are able to sublime this high-spin diradical under high vacuum at 140 °C with no significant decomposition.
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Triplet Ground State derivative of aza m xylylene diradical with large singlet Triplet energy gap
Journal of the American Chemical Society, 2011Co-Authors: Andrzej Rajca, Arnon Olankitwanit, Suchada RajcaAbstract:Organic molecules with a strong preference for Triplet Ground States, in which the Triplet State is below the lowest singlet State by ≥10 kcal/mol, are typically short-lived and mostly detected as reactive intermediates. We now report a Triplet Ground State derivative of aza-m-xylylene diradical with a large singlet−Triplet energy gap (ΔEST) of ∼10 kcal/mol, which is comparable to ΔEST for the well-known reactive intermediate m-xylylene diradical. The aminyl diradical persists in solution at room temperature on the time scale of minutes.
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Triplet Ground State Derivative of Aza-m-xylylene Diradical with Large Singlet−Triplet Energy Gap
Journal of the American Chemical Society, 2011Co-Authors: Andrzej Rajca, Arnon Olankitwanit, Suchada RajcaAbstract:Organic molecules with a strong preference for Triplet Ground States, in which the Triplet State is below the lowest singlet State by ≥10 kcal/mol, are typically short-lived and mostly detected as reactive intermediates. We now report a Triplet Ground State derivative of aza-m-xylylene diradical with a large singlet−Triplet energy gap (ΔEST) of ∼10 kcal/mol, which is comparable to ΔEST for the well-known reactive intermediate m-xylylene diradical. The aminyl diradical persists in solution at room temperature on the time scale of minutes.
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stable diarylnitroxide diradical with Triplet Ground State
Chemical Communications, 2009Co-Authors: Andrzej Rajca, Kouichi Shiraishi, Suchada RajcaAbstract:Nitroxide diradical 2, the first isolated diarylnitroxide diradical, is stable in the solid State at room temperature and it possesses Triplet Ground State with strong ferromagnetic coupling.
Andrzej Rajca - One of the best experts on this subject based on the ideXlab platform.
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thermally and magnetically robust Triplet Ground State diradical
Journal of the American Chemical Society, 2019Co-Authors: Nolan M Gallagher, Suchada Rajca, Hui Zhang, Tobias Junghoefer, Erika Giangrisostomi, Ruslan Ovsyannikov, Maren Pink, M B Casu, Andrzej RajcaAbstract:High spin (S = 1) organic diradicals may offer enhanced properties with respect to several emerging technologies, but typically exhibit low singlet Triplet energy gaps and possess limited thermal stability. We report Triplet Ground State diradical 2 with a large singlet–Triplet energy gap, ΔEST ≥ 1.7 kcal mol–1, leading to nearly exclusive population of Triplet Ground State at room temperature, and good thermal stability with onset of decomposition at ∼160 °C under inert atmosphere. Magnetic properties of 2 and the previously prepared diradical 1 are characterized by SQUID magnetometry of polycrystalline powders, in polystyrene glass, and in other matrices. Polycrystalline diradical 2 forms a novel one-dimensional (1D) spin-1 (S = 1) chain of organic radicals with intrachain antiferromagnetic coupling of J′/k = −14 K, which is associated with the N···N and N···O intermolecular contacts. The intrachain antiferromagnetic coupling in 2 is by far strongest among all studied 1D S = 1 chains of organic radicals...
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High-Spin Organic Diradical with Robust Stability
Journal of the American Chemical Society, 2016Co-Authors: Nolan M Gallagher, Suchada Rajca, Maren Pink, Jackson J. Bauer, Andrzej RajcaAbstract:Triplet Ground-State organic molecules are interesting with respect to several emerging technologies but typically exhibit limited stability. We report two organic diradicals, one of which possesses a Triplet Ground State (2J/kB = 234 ± 36 K) and robust stability at elevated temperatures. We are able to sublime this high-spin diradical under high vacuum at 140 °C with no significant decomposition.
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Triplet Ground State derivative of aza m xylylene diradical with large singlet Triplet energy gap
Journal of the American Chemical Society, 2011Co-Authors: Andrzej Rajca, Arnon Olankitwanit, Suchada RajcaAbstract:Organic molecules with a strong preference for Triplet Ground States, in which the Triplet State is below the lowest singlet State by ≥10 kcal/mol, are typically short-lived and mostly detected as reactive intermediates. We now report a Triplet Ground State derivative of aza-m-xylylene diradical with a large singlet−Triplet energy gap (ΔEST) of ∼10 kcal/mol, which is comparable to ΔEST for the well-known reactive intermediate m-xylylene diradical. The aminyl diradical persists in solution at room temperature on the time scale of minutes.
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Triplet Ground State Derivative of Aza-m-xylylene Diradical with Large Singlet−Triplet Energy Gap
Journal of the American Chemical Society, 2011Co-Authors: Andrzej Rajca, Arnon Olankitwanit, Suchada RajcaAbstract:Organic molecules with a strong preference for Triplet Ground States, in which the Triplet State is below the lowest singlet State by ≥10 kcal/mol, are typically short-lived and mostly detected as reactive intermediates. We now report a Triplet Ground State derivative of aza-m-xylylene diradical with a large singlet−Triplet energy gap (ΔEST) of ∼10 kcal/mol, which is comparable to ΔEST for the well-known reactive intermediate m-xylylene diradical. The aminyl diradical persists in solution at room temperature on the time scale of minutes.
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stable diarylnitroxide diradical with Triplet Ground State
Chemical Communications, 2009Co-Authors: Andrzej Rajca, Kouichi Shiraishi, Suchada RajcaAbstract:Nitroxide diradical 2, the first isolated diarylnitroxide diradical, is stable in the solid State at room temperature and it possesses Triplet Ground State with strong ferromagnetic coupling.
Martyn P. Coles - One of the best experts on this subject based on the ideXlab platform.
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cis-[Ni(Me6[14]trans-diene)(acac)]ClO4·0.167H2O, a folded macrocycle compound of Triplet Ground State [(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)nickel(II)]
Inorganica Chimica Acta, 2017Co-Authors: Neil F. Curtis, Martyn P. ColesAbstract:Abstract The preparation and structure of cis -1 RS ,8 RS -[(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)(pentan-2,4-dionato)nickel(II)] perchlorate 0.167 water are reported. This compound is the first reported example of this macrocycle in folded coordination to Triplet Ground State octahedrally coordinated nickel(II).
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cis ni me6 14 trans diene acac clo4 0 167h2o a folded macrocycle compound of Triplet Ground State 5 7 7 12 12 14 hexamethyl 1 4 8 11 tetraazacyclotetradec 4 11 diene nickel ii
Inorganica Chimica Acta, 2017Co-Authors: Neil F. Curtis, Martyn P. ColesAbstract:Abstract The preparation and structure of cis -1 RS ,8 RS -[(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)(pentan-2,4-dionato)nickel(II)] perchlorate 0.167 water are reported. This compound is the first reported example of this macrocycle in folded coordination to Triplet Ground State octahedrally coordinated nickel(II).
Neil F. Curtis - One of the best experts on this subject based on the ideXlab platform.
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cis-[Ni(Me6[14]trans-diene)(acac)]ClO4·0.167H2O, a folded macrocycle compound of Triplet Ground State [(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)nickel(II)]
Inorganica Chimica Acta, 2017Co-Authors: Neil F. Curtis, Martyn P. ColesAbstract:Abstract The preparation and structure of cis -1 RS ,8 RS -[(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)(pentan-2,4-dionato)nickel(II)] perchlorate 0.167 water are reported. This compound is the first reported example of this macrocycle in folded coordination to Triplet Ground State octahedrally coordinated nickel(II).
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cis ni me6 14 trans diene acac clo4 0 167h2o a folded macrocycle compound of Triplet Ground State 5 7 7 12 12 14 hexamethyl 1 4 8 11 tetraazacyclotetradec 4 11 diene nickel ii
Inorganica Chimica Acta, 2017Co-Authors: Neil F. Curtis, Martyn P. ColesAbstract:Abstract The preparation and structure of cis -1 RS ,8 RS -[(5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)(pentan-2,4-dionato)nickel(II)] perchlorate 0.167 water are reported. This compound is the first reported example of this macrocycle in folded coordination to Triplet Ground State octahedrally coordinated nickel(II).
Maren Pink - One of the best experts on this subject based on the ideXlab platform.
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thermally and magnetically robust Triplet Ground State diradical
Journal of the American Chemical Society, 2019Co-Authors: Nolan M Gallagher, Suchada Rajca, Hui Zhang, Tobias Junghoefer, Erika Giangrisostomi, Ruslan Ovsyannikov, Maren Pink, M B Casu, Andrzej RajcaAbstract:High spin (S = 1) organic diradicals may offer enhanced properties with respect to several emerging technologies, but typically exhibit low singlet Triplet energy gaps and possess limited thermal stability. We report Triplet Ground State diradical 2 with a large singlet–Triplet energy gap, ΔEST ≥ 1.7 kcal mol–1, leading to nearly exclusive population of Triplet Ground State at room temperature, and good thermal stability with onset of decomposition at ∼160 °C under inert atmosphere. Magnetic properties of 2 and the previously prepared diradical 1 are characterized by SQUID magnetometry of polycrystalline powders, in polystyrene glass, and in other matrices. Polycrystalline diradical 2 forms a novel one-dimensional (1D) spin-1 (S = 1) chain of organic radicals with intrachain antiferromagnetic coupling of J′/k = −14 K, which is associated with the N···N and N···O intermolecular contacts. The intrachain antiferromagnetic coupling in 2 is by far strongest among all studied 1D S = 1 chains of organic radicals...
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High-Spin Organic Diradical with Robust Stability
Journal of the American Chemical Society, 2016Co-Authors: Nolan M Gallagher, Suchada Rajca, Maren Pink, Jackson J. Bauer, Andrzej RajcaAbstract:Triplet Ground-State organic molecules are interesting with respect to several emerging technologies but typically exhibit limited stability. We report two organic diradicals, one of which possesses a Triplet Ground State (2J/kB = 234 ± 36 K) and robust stability at elevated temperatures. We are able to sublime this high-spin diradical under high vacuum at 140 °C with no significant decomposition.
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conformationally constrained stable Triplet Ground State s 1 nitroxide diradicals antiferromagnetic chains of s 1 diradicals
Journal of the American Chemical Society, 2007Co-Authors: Andrzej Rajca, Maren Pink, Masahiro Takahashi, Gaelle Spagnol, Suchada RajcaAbstract:Nitroxide diradicals, in which nitroxides are annelated to m-phenylene forming tricyclic benzobisoxazine-like structures, have been synthesized and characterized by X-ray crystallography, magnetic resonance (EPR and 1H NMR) spectroscopy, as well as magnetic studies in solution and in solid State. For the octamethyl derivative of benzobisoxazine nitroxide diradical, the conformationally constrained nitroxide moieties are coplanar with the m-phenylene, leading to large values of 2J (2J/k > 200 K in solution and 2J/k ≫ 300 K in the solid State). For the diradical, in which all ortho and para positions of the m-phenylene are sterically shielded, distortion of the nitroxide moieties from coplanarity is moderate, such that the singlet−Triplet gaps remain large in both solution (2J/k > 200 K) and the solid State (2J/k ≈ 400−800 K), though an onset of thermal depopulation of the Triplet Ground State is detectable near room temperature. These diradicals have robust Triplet Ground States with strong ferromagnetic c...
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Conformationally constrained, stable, Triplet Ground State (S = 1) nitroxide diradicals. Antiferromagnetic chains of S = 1 diradicals.
Journal of the American Chemical Society, 2007Co-Authors: Andrzej Rajca, Maren Pink, Masahiro Takahashi, Gaelle Spagnol, Suchada RajcaAbstract:Nitroxide diradicals, in which nitroxides are annelated to m-phenylene forming tricyclic benzobisoxazine-like structures, have been synthesized and characterized by X-ray crystallography, magnetic resonance (EPR and 1H NMR) spectroscopy, as well as magnetic studies in solution and in solid State. For the octamethyl derivative of benzobisoxazine nitroxide diradical, the conformationally constrained nitroxide moieties are coplanar with the m-phenylene, leading to large values of 2J (2J/k > 200 K in solution and 2J/k ≫ 300 K in the solid State). For the diradical, in which all ortho and para positions of the m-phenylene are sterically shielded, distortion of the nitroxide moieties from coplanarity is moderate, such that the singlet−Triplet gaps remain large in both solution (2J/k > 200 K) and the solid State (2J/k ≈ 400−800 K), though an onset of thermal depopulation of the Triplet Ground State is detectable near room temperature. These diradicals have robust Triplet Ground States with strong ferromagnetic c...
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Triplet s 1 Ground State aminyl diradical
Journal of the American Chemical Society, 2007Co-Authors: Andrzej Rajca, Kouichi Shiraishi, Maren Pink, Suchada RajcaAbstract:Aminyl diradical, which is stable in solution at low temperatures, is prepared. EPR spectra and SQUID magnetometry indicate that the diradical is planar and it possesses Triplet Ground State, with strong ferromagnetic coupling.
