Theoretical Studies on Effect of Conformation on the Spin Multiplicity Ground State in Parity Ethylene Type Biradical System and Stability

Abstract

Abstract: The effect of conformation on the spin multiplicity of ground state and it′s stability were investigated for parity ethylene type biradical system by means of comparative study with DFT, CASSCF and QCISD(T) methods. It is found that based on the continuous twisting of radical centers out of conjugation with the ethylene, both the absolute values and the tendency for the stability of triplet ground state (ΔE_S-T) of the investigated system change dramatically with variation the calculation methods. DFT and CASSCF methods cannot give a smooth change for ΔE_S-T, when the radical centers in the ethylene are twisted. However, the ΔE_S-T result obtained by QCISD(T) method offers a smooth change in the continuous twisting of radical centers. It is suggested that QCISD(T) method is reliable for dealing with the conformational problem of high-spin molecules. Furthermore, the ΔE_S-T values for ethylene type biradicals with one and two twisted radical centers were explored, respectively. When two or one radical centers in the ethylene are twisted sufficiently out of conjugation, and dihedral angles are close to 90°, ethylene turns into a weak antiferromagnet and weak ferromagnetic coupling units, respectively. Though the ethylene is a robust ferromagnetic coupling unit under planar conformation.

Key words: Parity ethylene, Biradical, DFT, CASSCF, QCISD(T), High-spin

CLC Number:

O641

TrendMD:

WANG Li-Min, ZHANG Jing-Ping, XUAN Yu-Shi, WANG Rong-Shun . Theoretical Studies on Effect of Conformation on the Spin Multiplicity Ground State in Parity Ethylene Type Biradical System and Stability[J]. Chem. J. Chinese Universities, 2004, 25(5): 913.

References

[1] Lah ti P.M.(Ed.).Mo lecular Properties of Organ ic Materials[M],New Yo rk:Dekker,1999 [2] Itoh K.,Kino sh ita M.(Eds).Mo lecular Magnetism New Magnetic Materials[M],Tokyo:Go rdon and Breach,2000 [3] Miller J.S.,Drillon M..Magnetism 2Mo lecules to Materials[M],Weinheim:Willey-V CH,2001 [4] WANG Qing-Lun(王庆伦),YAN Sh i-Ping(阎世平).Chem.J.Chinese Universities(高等学校化学学报)[J],2001,22(10), 1 632—1 633 [5] YAN Bing(闫　冰),WANG Shi-Xi(王诗玺),CHEN Zhi-Da(陈志达).Chem.J.Chinese Universities(高等学校化学学报)[J], 2001,22(2):167—170 [6] Miller J.S.,Ep stein A.J..Angew Chem.In t.Ed.Engl.[J],1994,33(4):385—415 [7] Rajca A..Chem.Rev.[J],1994,94(4):871—893 [8] Longuet-Higgin s H.C..J.Chem.Phys.[J],1950,18(3):265—274 [9] Ovch inn ikov A.A..Theo r.Ch im.Acta[J],1978,47(4):297—304 [10] Dow d P..Acc.Chem.Res.[J],1972,5(7):242—248 [11] Berson J.A..Acc.Chem.Res.[J],1978,11(2):446—453 [12] Dow d P..J.Am.Chem.Soc.[J],1966,88(11):2 587—2 589 [13] Steven J.Geib,Cristina Vicen t,Erkang Fan et al..Angew.Chem.,In t.Ed.Eng.l[J],1993,32(1):119—121 [14] Basem an R.J.,Pratt D.W.,Chow M.et al..J.Am.Chem.Soc.[J],1976,98(18):5 726—5 727 [15] Dixon D.A.,Dunn ing T.A..J.Am.Chem.Soc.[J],1981,103(10):2 878—2 880 [16] Hudson B.S.,Koh ler B.E.,Schulten K..Excited States[M],New Yo rk:E.C.Lim Ed.Academ ic Press,1982:54 [17] Longuet-Higgin s H.C.,Recto r C.W.,Platt J.R..J.Chem.Phys.[J],1950,18(9):1 174—1 181 [18] Gim aic B.M.,Ott J.J..J.Am.Chem.Soc.[J],1986,108(15):4 298—4 303 [19] Ott J.J.,Gim arc B.M..J.Am.Chem.Soc.[J],1986,108(15):4 303—4 308 [20] Lee C.,Yang W.,Parr R.G..Phys.Rev.[J],1988,B 37(2):785—789 [21] Hegarty D.,Robb M.A..Mo l.Phys.[J],1979,38(6):1 795—1 812 [22] Sch legel H.B.,Robb M.A..Chem.Phys.Lett.[J],1982,93(1):43—46 [23] Pop le J.A.,Head-Go rdon M.,Raghavachari K..J.Chem.Phys.[J],1987,87(10):5 968—5 975 [24] Heisenberg W..Z.Phys.[J],1928,49(3):619—636

Related Articles 15

[1]	HE Hongrui, XIA Wensheng, ZHANG Qinghong, WAN Huilin. Density-functional Theoretical Study on the Interaction of Indium Oxyhydroxide Clusters with Carbon Dioxide and Methane [J]. Chem. J. Chinese Universities, 2022, 43(8): 20220196.
[2]	WANG Yuanyue, AN Suosuo, ZHENG Xuming, ZHAO Yanying. Spectroscopic and Theoretical Studies on 5-Mercapto-1，3，4-thiadiazole-2-thione Microsolvation Clusters [J]. Chem. J. Chinese Universities, 2022, 43(10): 20220354.
[3]	YING Fuming, JI Chenru, SU Peifeng, WU Wei. λ-DFCAS： A Hybrid Density Functional Complete Active Space Self Consistent Field Method [J]. Chem. J. Chinese Universities, 2021, 42(7): 2218.
[4]	CAO Hongyu,MA Zihui,ZHANG Wenqiong,TANG Qian,LI Ruyu,ZHENG Xuefang. Structures and Electronic Absorption Spectra of N/Neo-Confused, Doubly N-Confused and Neo-Confused N-Confused Porphyrin Isomers ^† [J]. Chem. J. Chinese Universities, 2020, 41(2): 341.
[5]	WEI Xin, DENG Yaoliang, ZHENG Xuming, ZHAO Yanying. Ground Structure and Excited State Proton Transfer Reaction of 2-Aminobenzothiazole [J]. Chem. J. Chinese Universities, 2019, 40(8): 1679.
[6]	CAO Peiming,YOU Jinglin,ZHOU Candong,LU Liming,WANG Jian,WANG Min,DING Yani,XU Yandong. In-situ Studies of Microstructure of CaF₂-Al₂O₃-MgO Electroslag by Raman Spectroscopy and ²⁷Al MAS NMR^† [J]. Chem. J. Chinese Universities, 2019, 40(6): 1242.
[7]	LIU Qiuna,XU Wenwen,LIU Maozhu,WANG Huigang,ZHENG Xuming. Study on Raman Spectroscopy Non-coincidence Effect of Propionic Anhydride C=O Vibration Mode^† [J]. Chem. J. Chinese Universities, 2019, 40(5): 932.
[8]	ZHI Shasha,BAN Ying,XU Zhiguang,XU Xuan. Electron Transport of Metal String Complexes of [MM'M″(dpa)₄(Cl)₂](M=Co, Ni; M',M″=Co, Rh)^† [J]. Chem. J. Chinese Universities, 2019, 40(5): 980.
[9]	ZHOU Xiaofeng,ZHOU Yanbing,TANG Chunmei. Hydrogen Storage Capacity of the Alkaline Earth Metal Mg Exohedral Doped Boron Cage B₄₀M $g 6 †$ [J]. Chem. J. Chinese Universities, 2019, 40(3): 473.
[10]	ZHOU Hegen,JIN Hua,GUO Huirui,LIN Jing,ZHANG Yongfan. Electronic Structures and Optical Properties of Cu-based Semiconductors with Chalcopyrite-type Structure^† [J]. Chem. J. Chinese Universities, 2019, 40(3): 518.
[11]	YANG Meng, ZHANG Tengshuo, ZHENG Xuming, XUE Jiadan. Study on the Decay Dynamic of Excited State and Photodissociation Channel for 2-Nitronaphthalene^† [J]. Chem. J. Chinese Universities, 2018, 39(8): 1734.
[12]	YANG Yejin,YOU Jinglin,WANG Jian,WANG Min,HE Yingxia,WU Zhidong. In-situ High Temperature Raman Spectroscopic and Decomposition Thermodynamic Study of the Structure of Potassium Hydrogen Sulfate and Its Melt^† [J]. Chem. J. Chinese Universities, 2018, 39(10): 2272.
[13]	WANG Junkai, HAN Lei, HUANG Liang, ZHANG Haijun, LI Junyi, LI Saisai. Density Functional Theory Calculation and Experimental Study of Catalytic Synthesis SiC Nano Powders^† [J]. Chem. J. Chinese Universities, 2017, 38(9): 1602.
[14]	ZHANG Hui, ZHANG Hongmei, WANG Lianjun, SHEN Jinyou. Density Functional Theory Studies on the CO₂ Absorption by 1-Ethylamine-3-methylimidazolium Tetrafluoroborate^† [J]. Chem. J. Chinese Universities, 2016, 37(9): 1660.
[15]	MA Changmin, LIU Tingyu, CHANG Qiuxiang, LUO Guoyin. Theoretical Studies on the Intrinsic Defects in ZnO and ZnS Crystal^† [J]. Chem. J. Chinese Universities, 2016, 37(5): 932.