The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Ludwik Adamowicz - One of the best experts on this subject based on the ideXlab platform.
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lowest 2 s electronic excitations of the Boron Atom
Physical Review Letters, 2017Co-Authors: Sergiy Bubin, Ludwik AdamowiczAbstract:A theoretical ab initio approach for calculating bound states of small Atoms is developed and implemented. The approach is based on finite-nuclear-mass [non-Born-Oppenheimer (non-BO)] nonrelativistic variational calculations performed with all-particle explicitly correlated Gaussian functions and includes the leading relativistic and quantum electrodynamics energy corrections determined using the non-BO wave functions. The approach is applied to determine the total and transition energies for the lowest four $^{2}S$ electronic excitations of the Boron Atom. The transition energies agree with the available experimental values within $0.2--0.3\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$. Previously, such accuracy was achieved for three- and four-electron systems.
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explicitly correlated gaussian calculations of the 2d rydberg states of the Boron Atom
Journal of Chemical Physics, 2012Co-Authors: Keeper L Sharkey, Sergiy Bubin, Ludwik AdamowiczAbstract:Accurate non-relativistic variational calculations are performed for the seven lowest members of the 2D Rydberg series (1s22s2p2, and 1s22s2nd, n = 3, …, 8) of the Boron Atom. The wave functions of the states are expanded in terms of all-electron explicitly correlated Gaussian basis functions and the effect of the finite nuclear mass is directly included in the calculations allowing for determining the isotopic shifts of the energy levels. The Gaussian basis is optimized independently for each state with the aid of the analytic energy gradient with respect to the Gaussian parameters. The calculations represent the highest accuracy level currently achievable for the considered states. The computed energies are compared with the available experimental data.
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correlated gaussian calculations of the ground and low lying excited states of the Boron Atom
Physical Review A, 2011Co-Authors: Sergiy Bubin, Ludwik AdamowiczAbstract:Benchmark variational calculations of the four lowest {sup 2}P and {sup 2}S states of the Boron Atom (including the ground state) have been performed. The wave functions of the states have been expanded in terms of all-particle explicitly correlated Gaussian basis functions and the finite mass of the nucleus has been explicitly accounted for. Variational upper bounds for the nonrelativistic finite- and infinite-nuclear-mass energies of all considered states have been obtained with the relative convergence of the order of 10{sup -7}-10{sup -8}. Expectation values of the powers of the inter-particle distances and Dirac {delta} functions depending on those distances have also been computed. These calculations provide reference values that can be used to test other high-level quantum chemistry methods.
Chunhui Huang - One of the best experts on this subject based on the ideXlab platform.
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a novel three coordinate organoBoron derivative synthesis photophysical property and ion recognization
Tetrahedron Letters, 2007Co-Authors: Zhiguo Zhou, Chunhui HuangAbstract:Abstract A new push–pull type compound trans -4-dimesitylboryl-4′-(1,4,7,10-tetraoxa-13-aza-cyclopentadecyl) stilbene ( DBTS ) with aza-15-crown-5 as a donor and a three-coordinate organoBoron as an acceptor was designed and synthesized. DBTS shows intense fluorescence in a wide spectra range in different solvents. Furthermore, DBTS can recognize fluoride anions with a high selectivity for the special Lewis acid–base interaction between a trivalent Boron Atom and a fluoride anion. As a typical alkaline earth cations receptor, DBTS also showed spectral changes upon their addition.
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modulation of the photochromic property in an organoBoron based diarylethene by a fluoride ion
Organic Letters, 2006Co-Authors: Zhiguo Zhou, Shuzhang Xiao, Jia Xu, Fuyou Li, Tao Yi, Chunhui HuangAbstract:OrganoBoron-based diarylethene was successfully synthesized and exhibited photochromic property. Furthermore, its photochromic property can be modulated by a fluoride ion. The absorption maximum of the photostationary state shifted from 655 to 490 nm upon addition of a fluoride ion. The modulation mechanism is attributed to the special Lewis acid−base interaction between a trivalent Boron Atom and a fluoride ion.
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highly selective two photon chemosensors for fluoride derived from organic boranes
Organic Letters, 2005Co-Authors: Zhiqiang Liu, Mei Shi, Qi Fang, Zhanghai Chen, Chunhui HuangAbstract:Three organoBoron compounds are shown to be two-photon fluorescent sensors for fluoride anion with high sensitivity and selectivity. The recognition mechanism is attributed to the unique steric structure of the bulky dimesitylboryl group and the Lewis acid−base interaction between trivalent Boron Atom and fluoride anion.
Sergiy Bubin - One of the best experts on this subject based on the ideXlab platform.
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lowest 2 s electronic excitations of the Boron Atom
Physical Review Letters, 2017Co-Authors: Sergiy Bubin, Ludwik AdamowiczAbstract:A theoretical ab initio approach for calculating bound states of small Atoms is developed and implemented. The approach is based on finite-nuclear-mass [non-Born-Oppenheimer (non-BO)] nonrelativistic variational calculations performed with all-particle explicitly correlated Gaussian functions and includes the leading relativistic and quantum electrodynamics energy corrections determined using the non-BO wave functions. The approach is applied to determine the total and transition energies for the lowest four $^{2}S$ electronic excitations of the Boron Atom. The transition energies agree with the available experimental values within $0.2--0.3\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$. Previously, such accuracy was achieved for three- and four-electron systems.
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explicitly correlated gaussian calculations of the 2d rydberg states of the Boron Atom
Journal of Chemical Physics, 2012Co-Authors: Keeper L Sharkey, Sergiy Bubin, Ludwik AdamowiczAbstract:Accurate non-relativistic variational calculations are performed for the seven lowest members of the 2D Rydberg series (1s22s2p2, and 1s22s2nd, n = 3, …, 8) of the Boron Atom. The wave functions of the states are expanded in terms of all-electron explicitly correlated Gaussian basis functions and the effect of the finite nuclear mass is directly included in the calculations allowing for determining the isotopic shifts of the energy levels. The Gaussian basis is optimized independently for each state with the aid of the analytic energy gradient with respect to the Gaussian parameters. The calculations represent the highest accuracy level currently achievable for the considered states. The computed energies are compared with the available experimental data.
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correlated gaussian calculations of the ground and low lying excited states of the Boron Atom
Physical Review A, 2011Co-Authors: Sergiy Bubin, Ludwik AdamowiczAbstract:Benchmark variational calculations of the four lowest {sup 2}P and {sup 2}S states of the Boron Atom (including the ground state) have been performed. The wave functions of the states have been expanded in terms of all-particle explicitly correlated Gaussian basis functions and the finite mass of the nucleus has been explicitly accounted for. Variational upper bounds for the nonrelativistic finite- and infinite-nuclear-mass energies of all considered states have been obtained with the relative convergence of the order of 10{sup -7}-10{sup -8}. Expectation values of the powers of the inter-particle distances and Dirac {delta} functions depending on those distances have also been computed. These calculations provide reference values that can be used to test other high-level quantum chemistry methods.
Seung Soon Jang - One of the best experts on this subject based on the ideXlab platform.
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density functional theory modeling assisted investigation of thermodynamics and redox properties of Boron doped corannulenes for cathodes in lithium ion batteries
Journal of Physical Chemistry C, 2018Co-Authors: Jiwoong Kang, Ki Chul Kim, Seung Soon JangAbstract:Understanding thermodynamics and reduction potentials of Boron-doped corannulenes (BDCs) can provide meaningful insight to establish strategies for designing doping processes of organic materials applicable to cathodes in lithium-ion batteries (LIBs). In this study, a comprehensive set of BDC models is prepared to investigate the effect of the number and geometric position of doped Boron Atoms on the thermodynamic stability and redox properties of the corannulene. Our investigation enables us to evaluate their potential as organic cathode materials in LIBs. In this study, it is found that the first and second Boron Atoms can be exclusively doped in thermodynamically stable positions. Corannulene derivatives doped by the Boron Atom show enhanced reduction potentials ranged from 2.41 to 5.05 V vs Li/Li+ as compared with the pristine corannulene (0.9 V vs Li/Li+). A higher level of structural heterogeneity created by another Boron Atom does not guarantee a higher reduction potential (3.03 and 2.51 V vs Li/Li...
Laisheng Wang - One of the best experts on this subject based on the ideXlab platform.
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transition metal like bonding behaviors of a Boron Atom in a Boron cluster Boronyl complex η7 b7 b bo
Chemical Science, 2021Co-Authors: Wenjuan Tian, Weijia Chen, Miao Yan, Zhihong Wei, Tengteng Chen, Qiang Chen, Huajin Zhai, Laisheng WangAbstract:Boron displays many unusual structural and bonding properties due to its electron deficiency. Here we show that a Boron Atom in a Boron monoxide cluster (B9O−) exhibits transition-metal-like properties. Temperature-dependent photoelectron spectroscopy provided evidence of the existence of two isomers for B9O−: the main isomer has an adiabatic detachment energy (ADE) of 4.19 eV and a higher energy isomer with an ADE of 3.59 eV. The global minimum of B9O− is found surprisingly to be an umbrella-like structure (C6v, 1A1) and its simulated spectrum agrees well with that of the main isomer observed. A low-lying isomer (Cs, 1A′) consisting of a BO unit bonded to a disk-like B8 cluster agrees well with the 3.59 eV ADE species. The unexpected umbrella-like global minimum of B9O− can be viewed as a central Boron Atom coordinated by a η7-B7 ligand on one side and a BO ligand on the other side, [(η7-B7)-B-BO]−. The central B Atom is found to share its valence electrons with the B7 unit to fulfill double aromaticity, similar to that in half-sandwich [(η7-B7)-Zn-CO]− or [(η7-B7)-Fe(CO)3]− transition-metal complexes. The ability of Boron to form a half-sandwich complex with an aromatic ligand, a prototypical property of transition metals, brings out new metallomimetic properties of Boron.
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transition metal centered monocyclic Boron wheel clusters m bn a new class of aromatic borometallic compounds
Accounts of Chemical Research, 2013Co-Authors: Constantin Romanescu, Timur R Galeev, Weili Li, Alexander I Boldyrev, Laisheng WangAbstract:Atomic clusters have intermediate properties between that of individual Atoms and bulk solids, which provide fertile ground for the discovery of new molecules and novel chemical bonding. In addition, the study of small clusters can help researchers design better nanosystems with specific physical and chemical properties. From recent experimental and computational studies, we know that small Boron clusters possess planar structures stabilized by electron delocalization both in the σ and π frameworks. An interesting Boron cluster is B9–, which has a D8h molecular wheel structure with a single Boron Atom in the center of a B8 ring. This ring in the D8h-B9– cluster is connected by eight classical two-center, two-electron bonds. In contrast, the cluster’s central Boron Atom is bonded to the peripheral ring through three delocalized σ and three delocalized π bonds. This bonding structure gives the molecular wheel double aromaticity and high electronic stability. The unprecedented structure and bonding pattern i...
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hepta and octacoordinate Boron in molecular wheels of eight and nine Atom Boron clusters observation and confirmation
Angewandte Chemie, 2003Co-Authors: Huajin Zhai, Alexander I Boldyrev, Anastassia N Alexandrova, Alexander K Birch, Laisheng WangAbstract:Clusters of Atoms can adopt different Atomic arrangements from bulk materials. They often exhibit novel structures and properties, which provide opportunities for a new types of chemical bonding and stoichiometry. Herein we report experimental and theoretical evidence that 8- and 9-Atom Boron clusters are perfectly planar molecular wheels, with a hepta- or octacoordinated central Boron Atom, respectively, despite the predominance of three-dimensional structures normally found in bulk Boron and its compounds.