A5067707094- Boron Compounds in Chemistry
- Boron and Carbon Nanomaterials Research
- Metal-Organic Frameworks: Synthesis and Applications
- Radioactive element chemistry and processing
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advanced NMR Techniques and Applications
- Nanocluster Synthesis and Applications
- Thermal Expansion and Ionic Conductivity
- Luminescence and Fluorescent Materials
- Magnesium Oxide Properties and Applications
- Magnetism in coordination complexes
- Advanced Nanomaterials in Catalysis
- Machine Learning in Materials Science
- Chemical Synthesis and Characterization
- Advanced Battery Materials and Technologies
- Thermal properties of materials
- Lanthanide and Transition Metal Complexes
- Electron Spin Resonance Studies
- Orthopedic Infections and Treatments
- Covalent Organic Framework Applications
- Radiopharmaceutical Chemistry and Applications
- High-pressure geophysics and materials
University of California, Los Angeles
2022-2025
Sandia National Laboratories California
2018-2022
California NanoSystems Institute
2022
ConspectusIn this Account, we discuss our group's research over the past decade on a class of functionalized boron clusters with tunable chemical and physical properties, an emphasis accessing controlling their redox behavior. These can be thought as three-dimensional aromatic systems that have distinct behavior photophysical properties compared to two-dimensional organic counterparts. Specifically, lab has studied highly tunable, multielectron B12(OR)12 applied these molecules in various...
Several metal-organic frameworks are known to display negative thermal expansion (NTE). However, unlike traditional NTE material classes, there have been no reports where the of a MOF has tuned continuously from positive through formation single-phase solid solutions. In system Zn-DMOF-TMx, Zn2[(bdc)2-2x(TM-bdabco)2x][dabco], introduction increasing amounts TM-bdc, with four methyl groups decorating benzene dicarboxylate linker, leads smooth transition in a-b plane this tetragonal material....
Substituted two-dimensional aromatic systems, such as arenes, exhibit well-established reactivity patterns at specific sites, largely due to the pronounced electronic directing effects of attached substituents. In contrast, regioselectivity three-dimensional molecules a function substituents remains less understood and documented. this work, we demonstrate that series closo-dodecaborate ([B12H12]2-) cluster isomers containing two -NMe₃⁺ moieties unprecedented regioselective boron vertices...
We report the first experimental study into thermomechanical and viscoelastic properties of a metal-organic framework (MOF) material. Nanoindentations show decrease in Young's modulus, consistent with classical molecular dynamics simulations, hardness HKUST-1 increasing temperature over 25-100 °C range. Variable-temperature dynamic mechanical analysis reveals significant creep behavior, reduction 56% 88% 10 min at 25 100 °C, respectively. This result suggests that, despite increased density...
Herein, we report the use of sterically invariant carborane-based chalcogenols, containing exopolyhedral B–Se or B–S bonds, as ligands for formation photoluminescent copper(I)-based metal–organic chalcogenolate assemblies (MOCHAs). We show that precise tuning carborane dipole by changing isomer from meta to ortho allows control over MOCHA morphology and regulation resulting photophysical properties. Furthermore, microcrystal electron diffraction (MicroED) has been demonstrated a powerful...
Mechanisms underlying the mechanically induced amorphization of metal–organic frameworks (MOFs) are current interest, and both high-pressure experimentation molecular dynamics simulations have been used to reveal fundamentals load bearing, deformation, pressure-induced (PIA) in these highly porous materials. Unfortunately, MOFs typically susceptible amorphization, which limits conditions under they can be processed used. However, their flexible structures stabilized at high pressures by...
This work demonstrates the first successful electrochemical cycling of a redox-active boron cluster-based material in solid state. Specifically, we designed and synthesized an ether-functionalized dodecaborate cluster, B12(OCH3)12, which is smallest building block B12(OR)12 family. species can reversibly access four oxidation states solution, ranging from dianion to radical cation. We show that chemically isolated characterized neutral [B12(OCH3)12]0 cluster be utilized as cathode active...
Bioconjugation of polymers to proteins is a method impart improved stability and pharmacokinetic properties biologic systems. However, the precise effects polymer architecture on resulting bioconjugates are not well understood. Particularly, cyclic known possess unique features such as decreased hydrodynamic radius when compared their linear counterparts same molecular weight, but have yet been studied. Here, we report first bioconjugation polymer, poly(ethylene glycol) (PEG), model protein,...
The dynamic photoluminescence properties, and potential quenching mechanisms, of anti-B18H22, 4,4'-Br2-anti-B18H20, 4,4'-I2-anti-B18H20 are investigated in solution polymer films. UV stability studies the neat powders show no decomposition occurring after intense 7 day light soaking. In contrast, clusters incorporated into films found to degrade smaller borane fragments under same irradiation conditions. To highlight utility these compounds, we leverage their favorable optical properties a...
Four metalloporphyrinic metal-organic frameworks (MOFs) were successfully synthesized and exhibited enhanced activities for the photooxidation of a sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES). Among them, Sn-porphyrin functionalized 2D MOF, namely CSLA-21-NH
We report the synthesis and characterization of a 2D coordination polymer composed dianionic perhydroxylated boron cluster, [B 12 (OH) 2− ], coordinated to Zn( ii )—the first example transition metal-coordinated ] compound.
In this work, we discuss the synthesis and characterization of a 2D coordination polymer composed dianionic perhydroxylated boron cluster, [B12(OH)122-], coordinated to Zn(II)—the first example transition metal-coordinated [B12(OH)12]2- compound. This material was synthesized via cation exchange from starting cesium salt then subjected rigorous characterizion prior after thermal activation. Numerous techniques, including XRD, FTIR, SEM, TGA, solid-state NMR revealed sheets Zn(II) ions...
This work demonstrates the first successful electrochemical cycling of a redox-active boron cluster-based material in solid state. Specifically, we designed and synthesized an ether-functionalized dodecaborate cluster, B12(OCH3)12, which is smallest building block B12(OR)12 family. species can reversibly access four oxidation states solution, ranging from dianion to radical cation. We show that chemically isolated characterized neutral [B12(OCH3)12]0 cluster be utilized as cathode active...
Herein, we report the use of sterically invariant carborane-based chalcogenols, containing exopolyhedral B-Se or B-S bonds, as ligands for formation photoluminescent copper(I)-based metal-organic chalcogenolate assemblies (MOCHAs). We show that precise tuning carborane dipole by changing isomer from meta- to ortho- allows control over MOCHA morphology and regulation resulting photophysical properties. Furthermore, microcrystal electron diffraction (MicroED) has been demonstrated a powerful...
The dynamic photoluminescent properties, and potential quenching mechanisms, of anti-B18H22, 4,4’-Br2-anti-B18H20, 4,4’-I2-anti-B18H20 are investigated in solution polymer films. UV stability studies the neat powders show no decomposition occurring after intense 7 day light soaking. In contrast, clusters incorporated into films found to degrade smaller borane fragments under same irradiation conditions. To highlight utility these compounds, we leverage their favorable optical properties a...