文献类型：期刊文献

英文题名：Amine Dynamics in Diamine-Appended Mg2(dobpdc) Metal-Organic Frameworks

作者：Xu, Jun[1,2,3];Liu, Yifei Michelle[3];Lipton, Andrew S.[6];Ye, Jinxing[3,4,7];Hoatson, Gina L.[8];Milner, Phillip J.[4,10];McDonald, Thomas M.[4,10];Siegelman, Rebecca L.[4,10];Forse, Alexander C.[3,4,5];Smit, Berend[3,9];Long, Jeffrey R.[3,4,10];Reimer, Jeffrey A.[3,10]

机构：[1]Nankai Univ, Sch Mat Sci & Engn, Ctr Rare Earth & Inorgan Funct Mat, Tianjin Key Lab Rare Earth Mat & Applicat, Tianjin 300350, Peoples R China;[2]Nankai Univ, Natl Inst Adv Mat, Tianjin 300350, Peoples R China;[3]Univ Calif Berkeley, Dept Chem & Biomol Engn, Berkeley, CA 94720 USA;[4]Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA;[5]Univ Calif Berkeley, Berkeley Energy & Climate Inst, Berkeley, CA 94720 USA;[6]Pacific Northwest Natl Lab, Environm Mol Sci Lab, 902 Battelle Blvd, Richland, WA 99354 USA;[7]East China Univ Sci & Technol, Sch Pharm, Engn Res Ctr Pharmaceut Proc Chem, Minist Educ, 130 Meilong Rd, Shanghai 200237, Peoples R China;[8]Coll William & Mary, Dept Phys, POB 8795, Williamsburg, VA 23187 USA;[9]Valais Ecole Polytech Fed Lausanne EPFL, Lab Mol Simulat, Inst Sci & Ingn Chim, Rue Ind 17, CH-1951 Sion, Switzerland;[10]Lawrence Berkeley Natl Lab, Mat Sci Div, Berkeley, CA 94720 USA

年份：2019

卷号：10

期号：22

起止页码：7044

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY LETTERS

收录：;EI(收录号：20194607665970);WOS:【SCI-EXPANDED(收录号:WOS:000497261200013)】；

基金：This work was supported through the Center for Gas Separations Relevant to Clean Energy Technologies, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award DE-SC0001015. Some 15N SSNMR experiments were performed at the Environmental Molecular Sciences Laboratory, a DOE Office of Science User Facility sponsored by the Office of Biological and Environmental Research. DFT calculations were performed at the Molecular Graphics and Computation Facility at UC Berkeley, which is funded by the U.S. National Institutes of Health under Award S10OD023532. The MD simulations were carried out at the National Energy Research Scientific Computing Center, a User Facility supported by the Office of Science of the U.S. Department of Energy under Contract DE-AC02-05CH11231. Y.M.L. thanks the NSF Graduate Research Fellowship program. P.J.M. thanks the National Institute of General Medical Sciences of the National Institutes of Health for a postdoctoral fellowship. J.X. acknowledges the financial support from the National Natural Science Foundation of China (Project 21904071) and the Open Funds (KF1818) of the State Key Laboratory of Fine Chemicals. We thank Dr. Jeffrey Martell for experimental assistance and fruitful discussions and Dr. Katie Meihaus for editorial assistance.

语种：英文

外文关键词：Carboxylation - Bond strength (materials) - Nuclear magnetic resonance spectroscopy - Molecular dynamics - Activation energy - Carbon dioxide - Magnesium compounds - Organic polymers - Density functional theory - Light polarization - Monte Carlo methods - Metals - Organometallics

摘要：Variable-temperature N-15 solid-state NMR spectroscopy is used to uncover the dynamics of three diamines appended to the metal-organic framework Mg-2(dobpdc) (dobpdc(4-) = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate), an important family of CO2 capture materials. The results imply both bound and free amine nitrogen environments exist when diamines are coordinated to the framework open Mg2+ sites. There are rapid exchanges between two nitrogen environments for all three diamines, the rates and energetics of which are quantified by N-15 solid-state NMR data and corroborated by density functional theory calculations and molecular dynamics simulations. The activation energy for the exchange provides a measure of the metal-amine bond strength. The unexpected negative correlation between the metal-amine bond strength and CO2 adsorption step pressure reveals that metal-amine bond strength is not the only important factor in determining the CO2 adsorption properties of diamine-appended Mg-2(dobpdc) metal-organic frameworks.