N,N-B螯合物光物理性质的密度泛函理论研究

doi:10.7503/cjcu20141054

摘要/Abstract

摘要：

采用密度泛函理论(DFT)和含时密度泛函理论(TD-DFT)方法计算了4种N,N-B螯合物1, 1q, 2和2q的基态和激发态结构、吸收和发射光谱、跃迁密度矩阵、分子内电荷转移特征、黄昆(HR)因子、 Franck-Condon因子和电子耦合等光物理性质, 深入探究化合物1q和2q在几何结构微调后发光效率降低的本质原因. 计算结果表明, N,N-B螯合物中喹啉取代吡啶, 以及吲哚配体中N杂原子的引入对光物理性质产生了较大影响. 相比于化合物1和2, 化合物1q和2q由于共轭面的扩展导致HOMO-LUMO能隙变窄, 使吸收红移. 通过计算HR因子和跃迁密度矩阵对激发态的特征和几何弛豫进行分析, 结果表明化合物1q和2q具有明显增强的片段间电荷转移特征, 发射能和振子强度减弱导致k_r减小, 并且激发态和基态间的电子耦合急剧增强造成快速的非辐射衰变, 导致化合物1q和2q在CH₂Cl₂溶液中不发光. 同时, 化合物1和2具有高效的发光效率和较大的斯托克斯位移, 是一类有发展前景的发光材料.

关键词: 光物理性质, 吸收光谱, 发光效率, 有机硼化物, 密度泛函理论

Abstract:

The photophysical properties of four N,N-chelate boron complexes 1, 1q, 2 and 2q, including the geometric structures of the ground and excited state, absorption and emission spectra, transition density matrices(TDM), intramolecular charge transfer, Huang-Rhys(HR) factors, Franck-Condon factors and electronic coupling, were investigated with density functional theory(DFT) and time-dependent DFT(TD-DFT) calculations to shed light on the origin of the apparent decrease in the luminescence efficiency of complexes 1q and 2q due to the tiny modification. The computed results show that the substitution of quinolyl ligand and the incorporation of N-heteroatom significantly influence the photophysical properties of these complexes. Complexes 1q and 2q show a relatively narrower HOMO-LUMO energy gap owing to the extended conjugation, thus leading to a redshift absorption wavelength. An in-depth insight into HR factors and TDM is provided to inspect the geometric distortions and the character of excited states pertaining to absorption. The computed results indicate that complexes 1q and 2q show dramatically enhanced charge transfer between fragments, and the decreased emission energy and oscillator strength lead to a smaller radiative rate constant. Furthermore, the sharp enhanced electronic coupling between the excited and ground state results in fast non-radiative decay, thus complexes 1q and 2q are not luminescent in CH₂Cl₂. In addition, complexes 1 and 2 show great potential application as emitters as they display relatively high luminescence efficiency and large stokes shift.

Key words: Photophysical property, Absorption spectrum, Luminescent efficiency, Organoboron, Density functional theory

中图分类号:

O641

TrendMD:

靳俊玲, 丁祥, 欧利辉, 张向阳, 申有名, 耿允, 苏忠民. N,N-B螯合物光物理性质的密度泛函理论研究. 高等学校化学学报, 2015, 36(5): 962.

JIN Junling, DING Xiang, OU Lihui, ZHANG Xiangyang, SHEN Youming, GENG Yun, SU Zhongmin. Density Functional Theory Studies on the Photophysical Properties of N,N-Chelate Boron Complexes^†. Chem. J. Chinese Universities, 2015, 36(5): 962.

图/表 8

Fig.1 Molecular structures for complexes 1, 1q, 2 and 2q

Fig.2 Illustration of the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) plots, the orbi-tal energy levels, and the HOMO-LUMO energy gaps for complexes 1, 1q, 2 and 2q at their optimized S0 geometries in vacuum at B3LYP/6-31G(d) levelThe molecular orbital plots were obtained with an isosurface of 0.02 a.u.

Table 1 Calculated absorption wavelengths(λabs), excitation energies(Ex), oscillator strengths f, and dominant excitation character of complexes 1, 2, 1q, and 2q together with experimental results(λexp.)*

Complex	Transition	λ_abs/nm	E_x/eV	f	Composition	λ_exp./nm
1	S₀→S₁	353.9	3.503	0.367	HOMO→LUMO(98%)	378
1q	S₀→S₁	431.8	2.872	0.207	HOMO→LUMO(98%)	450
2	S₀→S₁	343.5	3.610	0.515	HOMO→LUMO(99%)	374
2q	S₀→S₁	419.8	2.954	0.237	HOMO→LUMO(99%)	446

Table 2 Calculated emission wavelengths(λem), emission energies(Em), oscillator strengths f, dominant excitation character, Stokes shift(SS), radiative rate constants(kr) and nonradiative rate constants(knr) of complexes 1, 2, 1q, and 2q together with the reported experimental results of the emission wavelength(λexp.) and quantum yield(Φexp.)a

Complex	Transition	λ_em/nm	E_m/eV	f	Composition	SS/nm	k_r/s^-1	k_nr/s^-1	Φ_exp.	λ_exp./nm
1	S₁→S₀	410.2	3.022	0.128	LUMO→HOMO(98%)	56.3	5.10×10⁷	1.02×10⁷	0.29^b	516
1q	S₁→S₀	538.5	2.302	0.060	LUMO→HOMO(99%)	96.7	1.40×10⁷	2.46×10¹⁰	N/A^c	578
2	S₁→S₀	400.1	3.099	0.185	LUMO→HOMO(99%)	56.6	7.70×10⁷	0.99×10⁷	0.61^b	476
2q	S₁→S₀	521.9	2.376	0.080	LUMO→HOMO(99%)	102.1	2.00×10⁷	2.62×10¹⁰	N/A^c	546

Fig.3 Transition density matrix of the hot excitation(S0 state) for complexes 1(A, A'), 1q(B, B'), 2(C, C') and 2q(D, D') calculated by B3LYP/6-31G(2d,p) in vacuumThe unit of color scale is a.u.2, 1 a.u.=1.6×10-19 C.

Fig.4 Calculated results for the centroids of charge(C+/C-) and the charge-transfer distance(DCT) between the barycenters of density depletion(gray) and density increment(purple) zone, and the transferred charge(Δq) computed for the first electronic transitionThe calculation level is B3LYP/6-31G(2d,p) level.

Fig.5 Calculated HR factors and the normal mode for complexes 1(A), 1q(B), 2(C) and 2q(D)

Fig.6 Calculated R2/ћ and the normal mode for complexes 1(A), 1q(B), 2(C) and 2q(D)

参考文献 30

[1]	Lorbach, A. , Hubner, A. , Wagner, M. , Dalton Trans., 2012, 41( 20), 6048- 6063
[2]	Li, D. , Wang, K. , Huang, S. , Qu, S. , Liu, X. , Zhu, Q. , Zhang, H. , Wang, Y. , J. Mater. Chem., 2011, 21( 39), 15298- 15304
[3]	Mizuno, Y. , Yisilamu, Y. , Yamaguchi, T. , Tomura, M. , Funaki, T. , Sugihara, H. , Ono, K. , Chem. Eur. J., 2014, 20( 41), 13286- 13295
[4]	Kojima, T. , Kumaki, D. , Nishida J., I. , Tokito, S. , Yamashita, Y. , J. Mater. Chem., 2011, 21( 18), 6607- 6613
[5]	Awuah S., G. , You, Y. , RSC Advances, 2012, 2( 30), 11169- 11183
[6]	Boens, N. , Leen, V. , Dehaen, W. , Chem. Soc. Rev., 2012, 41( 3), 1130- 1172
[7]	Ulrich, G. , Ziessel, R. , Harriman, A. , Angew. Chem. Int. Ed., 2008, 47( 7), 1184- 1201
[8]	Yoshii, R. , Tanaka, K. , Chujo, Y. , Macromolecules, 2014, 47( 7), 2268- 2278
[9]	Massue, J. , Frath, D. , Retailleau, P. , Ulrich, G. , Ziessel, R. , Chem. Eur. J., 2013, 19( 17), 5375- 5386
[10]	Chambon, S. , D'Aleo, A. , Baffert, C. , Wantz, G. , Fages, F. , Chem. Comm., 2013, 49( 34), 3555- 3557
[11]	Wakamiya, A. , Taniguchi, T. , Yamaguchi, S. , Angew. Chem. Int. Ed., 2006, 45( 19), 3170- 3173
[12]	Nagura, K. , Saito, S. , Frö, hlich R. , Glorius, F. , Yamaguchi, S. , Angew. Chem., 2012, 124( 31), 7882- 7886
[13]	Brö, ring M. , Krü, ger R. , Link, S. , Kleeberg, C. , Kö, hler S. , Xie, X. , Ventura, B. , Flamigni, L. , Chem. Eur. J., 2008, 14( 10), 2976- 2983
[14]	Hao, Q. , Yu, S. , Li, S. , Chen, J. , Zeng, Y. , Yu, T. , Yang, G. , Li, Y. , J. Org. Chem., 2013, 79( 1), 459- 464
[15]	Mao, M. , Wang J., B. , Xiao Z., F. , Dai S., Y. , Song Q., H. , Dyes Pigments, 2012, 94( 2), 224- 232
[16]	Suresh, D. , Gomes C. S., B. , Gomes P., T. , Di Paolo R., E. , Macanita A., L. , Calhorda M., J. , Charas, A. , Morgado, J. , Teresa Duarte, M. , Dalton Trans., 2012, 41( 28), 8502- 8505
[17]	Calhorda M., J. , Suresh, D. , Gomes P., T. , Di Paolo R., E. , Macanita A., L. , Dalton Trans., 2012, 41( 42), 13210- 13217
[18]	Liu, H. , Lu, H. , Xu, J. , Liu, Z. , Li, Z. , Mack, J. , Shen, Z. , Chem. Comm., 2014, 50( 9), 1074- 1076
[19]	Liu Q., D. , Mudadu M., S. , Thummel, R. , Tao, Y. , Wang, S. , Adv. Funct. Mater., 2005, 15( 1), 143- 154
[20]	Le Guennic, B. , Chibani, S. , Charaf-Eddin, A. , Massue, J. , Ziessel, R. , Ulrich, G. , Jacquemin, D. , Phys. Chem. Chem. Phys., 2013, 15( 20), 7534- 7540
[21]	李倩, 耿允, 段雨爱, 王光宇, 苏忠民. 高等学校化学学报, 2014, 35( 7), 1471- 1479
	Li, Q. , Geng, Y. , Duan Y., A. , Wang G., Y. , Su Z., M. , Chem. J. Chinese Universities, 2014, 35( 7), 1471- 1479
[22]	苏欣, 张吉, 吴勇, 耿允, 苏忠民. 高等学校化学学报, 2013, 34( 8), 1945- 1952
	Su, X. , Zhang, J. , Wu, Y. , Geng, Y. , Su Z., M. , Chem. J. Chinese Universities , 2013, 34( 8), 1945- 1952
[23]	Teng Y., L. , Kan Y., H. , Su Z., M. , Liao, Y. , Yang S., Y. , Wang R., S. , Theo. Chem. Acc., 2007, 117( 1), 1- 5
[24]	Yang, G. , Su, T. , Shi, S. , Su, Z. , Zhang, H. , Wang, Y. , J. Phys. Chem. A, 2007, 111( 14), 2739- 2744
[25]	Lu T. ,
[26]	Lu, T. , Chen, F. , J. Comput. Chem., 2012, 33( 5), 580- 592
[27]	Frisch M., J. , Trucks G., W. , Schlegel H., B. , Scuseria G., E. , Robb M., A. , Cheeseman J., R. , Scalmani, G. , Barone, V. , Mennucci, B. , Petersson G., A. , Nakatsuji, H. , Caricato, M. , Li, X. , Hratchian H., P. , Izmaylov A., F. , Bloino, J. , Zheng, G. , Sonnenberg J., L. , Hada, M. , Ehara, M. , Toyota, K. , Fukuda, R. , Hasegawa, J. , Ishida, M. , Nakajima, T. , Honda, Y. , Kitao, O. , Nakai, H. , Vreven, T. , Montgomery J. A., Jr. , Peralta J., E. , Ogliaro, F. , Bearpark, M. , Heyd J., J. , Brothers, E. , Kudin K., N. , Staroverov V., N. , Kobayashi, R. , Normand, J. , Raghavachari, K. , Rendell, A. , Burant J., C. , Iyengar S., S. , Tomasi, J. , Cossi, M. , Rega, N. , Millam J., M. , Klene, M. , Knox J., E. , Cross J., B. , Bakken, V. , Adamo, C. , Jaramillo, J. , Gomperts, R. , Stratmann R., E. , Yazyev, O. , Austin A., J. , Cammi, R. , Pomelli, C. , Ochterski J., W. , Martin R., L. , Morokuma, K. , Zakrzewski V., G. , Voth G., A. , Salvador, P. , Dannenberg J., J. , Dapprich, S. , Daniels A., D. , Farkas, O. , Foresman J., B. , Ortiz J., V. , Cioslowski, J. , Fox D., J. , Gaussian, 09W , Revision A.02. Gaussian, Inc. , Wallingford CT, 2009
[28]	Li M., C. , Hayashi, M. , Lin S., H. , J. Phys. Chem. A, 2011, 115( 50), 14531- 14538
[29]	Jin J., L. , Li H., B. , Geng, Y. , Wu, Y. , Duan Y., A. , Su Z., M. , ChemPhysChem, 2012, 13( 16), 3714- 3722
[30]	Yin, S. , Peng, Q. , Shuai, Z. , Fang, W. , Wang Y., H. , Luo, Y. , Phys. Rev. B, 2006, 73( 20), 205409/ 1- 205409/5

相关文章 15

[1]	何鸿锐, 夏文生, 张庆红, 万惠霖. 羟基氧化铟团簇与二氧化碳和甲烷作用的密度泛函理论研究[J]. 高等学校化学学报, 2022, 43(8): 20220196.
[2]	黄汉浩, 卢湫阳, 孙明子, 黄勃龙. 石墨炔原子催化剂的崭新道路:基于自验证机器学习方法的筛选策略[J]. 高等学校化学学报, 2022, 43(5): 20220042.
[3]	刘洋, 李旺昌, 张竹霞, 王芳, 杨文静, 郭臻, 崔鹏. Sc₃C₂@C₈₀与[12]CPP纳米环之间非共价相互作用的理论研究[J]. 高等学校化学学报, 2022, 43(11): 20220457.
[4]	周成思, 赵远进, 韩美晨, 杨霞, 刘晨光, 贺爱华. 硅烷类外给电子体对丙烯-丁烯序贯聚合的调控作用[J]. 高等学校化学学报, 2022, 43(10): 20220290.
[5]	程媛媛, 郗碧莹. ·OH自由基引发CH₃SSC $H 3 •$ ⁺自由基裂解反应机理的理论研究[J]. 高等学校化学学报, 2022, 43(10): 20220271.
[6]	王园月, 安梭梭, 郑旭明, 赵彦英. 5-巯基-1, 3, 4-噻二唑-2-硫酮微溶剂团簇的光谱和理论计算研究[J]. 高等学校化学学报, 2022, 43(10): 20220354.
[7]	马丽娟, 高升启, 荣祎斐, 贾建峰, 武海顺. Sc, Ti, V修饰B/N掺杂单缺陷石墨烯的储氢研究[J]. 高等学校化学学报, 2021, 42(9): 2842.
[8]	钟声广, 夏文生, 张庆红, 万惠霖. 电中性团簇MCu₂O_x(M=Cu²⁺, Ce⁴⁺, Zr⁴⁺)上甲烷和二氧化碳直接合成乙酸的理论研究[J]. 高等学校化学学报, 2021, 42(9): 2878.
[9]	黄罗仪, 翁约约, 黄旭慧, 王朝杰. 车前草中黄酮类成分结构和性质的理论研究[J]. 高等学校化学学报, 2021, 42(9): 2752.
[10]	王建, 张红星. 四配位铂磷光发射体结构与光物理性质关系的理论研究[J]. 高等学校化学学报, 2021, 42(7): 2245.
[11]	胡伟, 刘小峰, 李震宇, 杨金龙. 金刚石纳米线氮空位色心的表面与尺寸效应[J]. 高等学校化学学报, 2021, 42(7): 2178.
[12]	杨一莹, 朱荣秀, 张冬菊, 刘成卜. 金催化炔基苯并二𫫇英环化合成8-羟基异香豆素的理论研究[J]. 高等学校化学学报, 2021, 42(7): 2299.
[13]	柳扬, 李清波, 孙杰, 赵显. Ga对在AlN衬底上直接生长石墨烯的远程催化[J]. 高等学校化学学报, 2021, 42(7): 2271.
[14]	程效, BORA Debajeet K., Per⁃Anders, GUO Jinghua, 罗毅. 理论研究晶体场效应和电荷转移效应对Co²⁺的2p电子X射线L_2,3吸收边光谱的影响[J]. 高等学校化学学报, 2021, 42(7): 2197.
[15]	郑若昕, 张颖, 徐昕. 低标度XYG3双杂化密度泛函的开发与测评[J]. 高等学校化学学报, 2021, 42(7): 2210.