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1.
DFT B3LYP/LANL2DZ method was employed to calculate electron properties and the second-order nonlinear optical (NLO) respond
of platinum (II) complexes which have been synthesized by Weinstein group. 4,7-diphenyl-1,10-phenanthroline shows the ability
to push electron in these complexes. Metal Pt plays a balancing charge role. Comparing complex 1b–6b with complex a, the βvec value of complex 1b–5b is larger than one of complex a, while the βvec value of complex 6b is smaller than one of complex a. In these seven complexes, the βvec values of complexes increase with decreasing of the energy difference between HOMO and LUMO. Moreover, the electron transfers
from deeper layer occupied orbitals to empty orbitals have a distinct contribution to second-order NLO coefficient.
Supported by Program for Changjiang Scholars and Innovative Research Team in University, the Foundation of Jilin Provincial
Excellent Youth (Grant No. 20050107) and Youth Science Foundation of Northeast Normal University (Grant No. 111494117) 相似文献
2.
Min Zhang Yan Li Ze‐Sheng Li Jia‐Zhong Sun 《International journal of quantum chemistry》2010,110(6):1142-1151
The geometries, energies, and electronic properties of a series of phosphorescent Pt(II) complexes including FPt, CFPt, COFPt, and NFPt have been characterized within density functional theory DFT calculations which can reproduce and rationalize experimental results. The properties of excited‐states of the Pt(II) complexes were characterized by configuration interaction with singles (CIS) method. The ground‐ and excited‐state geometries were optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ levels, respectively. In addition, we also have performed a triplet UB3LYP optimization for complex FPt and compared it with CIS method in the emission properties. The datum (562.52 nm) of emission wavelength for complex FPt, which were computed based on the triplet UB3LYP optimization excited‐state geometry, is not agreement with the experiment value (500 nm). The absorption and phosphorescence wavelengths were computed based on the optimized ground‐ and excited‐state geometries, respectively, by the time‐dependent density functional theory (TD‐DFT) methods. The results revealed that the nature of the substituent at the phenylpyridine ligand can influence the distributions of HOMO and LUMO and their energies. Moreover, the auxiliary ligand pyridyltetrazole can make the molecular structure present a solid geometry. In addition, the charge transport quality has been estimated approximately by the predicted reorganization energy (λ). Our result also indicates that the substitute groups and different auxiliary ligand not only change the nature of transition but also affect the rate and balance of charge transfer. By summarizing the results, we can conclude that the NFPt is good OLED materials with a solid geometry and a balanced charge transfer rate. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
3.
G. O. Finagenova A. A. Nikiforova M. V. Puzyk K. P. Balashev 《Russian Journal of General Chemistry》2008,78(9):1780-1786
1H NMR spectroscopy, electronic absorption and emission spectroscopy, and cyclic voltammetry were used for comparative study of the complexes [M(ppy)(dpz)]ClO4, [M(ppy)ddpq]ClO4, and [(M(ppy)2(μ-tpbq)](ClO4)2 (M = Pt(II), Pd(II); ppy? = deprotonated 2-phenylpyridine; dpz = 2,3-dipirydylpyrazine, ddpq = 6,7-dimethyl-2,3-dipyridylquinoxaline, tpbq = 2,2′,3,3′-tetrapyridyl-6,6′-biquinoline). The complexes feature trans arrangement of the pyridine moieties of the cyclometalated ppy and polypyridyl (N∧N) ligands. Steric interactions orient the noncoordinated pyridine moiety of the (N∧N) ligands orthogonally to the coordination plane of the complexes. One-electron reduction potentials and parameters of the absorption and luminescence spectra of the complexes were determined. It was shown in terms of the localized molecular orbital model that the LUMOs of the [M(ppy)dpz]+ complexes are primarily localized on the {M(ppy)} metal complex fragment. The presence of low-energy vacant π* orbitals in ddpq and tpbq results in that the LUMOs in the [M(ppy)ddpq] and [(M(ppy)2 μ-tpbq]2+ complexes are localized on the polypyridyl (N∧N) ligand, which is responsible for highly efficient photoexcitation energy transfers [M(ppy)→ddpq]+ and [M(ppy) → (μ-tpbq)←M(ppy)]2+. 相似文献
4.
Janzen DE Vanderveer DG Mehne LF da Silva Filho DA Brédas JL Grant GJ 《Dalton transactions (Cambridge, England : 2003)》2008,(14):1872-1882
We report the synthesis and full characterization for a series of cyclometallated complexes of Pt(II) and Pd(II) incorporating the fluxional trithiacrown ligand 1,4,7-trithiacyclononane ([9]aneS3). Reaction of [M(C insertion mark N)(micro-Cl)]2 (M = Pt(II), Pd(II); C insertion mark N = 2-phenylpyridinate (ppy) or 7,8-benzoquinolinate (bzq)) with [9]aneS3 followed by metathesis with NH4PF6 yields [M(C insertion mark N)([9]aneS3)](PF6). The complexes [M(C insertion mark P)([9]aneS3)](PF6) (M = Pt(II), Pd(II); Cinsertion markP = [CH2C6H4P(o-tolyl)2-C,P]-) were synthesized from their respective [Pt(C insertion mark P)(micro-Cl)]2 or [Pd(C insertion mark P)(micro-O2CCH3)]2 (C insertion mark P) starting materials. All five new complexes have been fully characterized by multinuclear NMR, IR and UV-Vis spectroscopies in addition to elemental analysis, cyclic voltammetry, and single-crystal structural determinations. As expected, the coordinated [9]aneS3 ligand shows fluxional behavior in its NMR spectra, resulting in a single 13C NMR resonance despite the asymmetric coordination environment of the cyclometallating ligand. Electrochemical studies reveal irreversible one-electron metal-centered oxidations for all Pt(II) complexes, but unusual two-electron reversible oxidations for the Pd(II) complexes of ppy and bzq. The X-ray crystal structures of each complex indicate an axial M-S interaction formed by the endodentate conformation of the [9]aneS3 ligand. The structure of [Pd(bzq)([9]aneS3)](PF6) exhibits disorder in the [9]aneS3 conformation indicating a rare exodentate conformation as the major contributor in the solid-state structure. DFT calculations on [Pt([9]aneS3)(ppy)](PF6) and [Pd([9]aneS3)(ppy)](PF6) indicate the HOMO for both complexes is primarily dz2 in character with a significant contribution from the phenyl ring of the ppy ligand and p orbital of the axial sulfur donor. In contrast, the calculated LUMO is primarily ppy pi* in character for [Pt([9]aneS3)(ppy)](PF6), but dx2-y2 in character for [Pd([9]aneS3)(ppy)](PF6). 相似文献
5.
Sarju J Arbour J Sayer J Rohrmoser B Scherer W Wagner G 《Dalton transactions (Cambridge, England : 2003)》2008,(39):5302-5312
The nitrile ligands in trans-[PtX2(PhCN)2] (X = Cl, Br, I) undergo sequential 1,3 dipolar cycloadditions with nitrones R1R2C=N+(Me)-O(-) (R1 = H, R2 = Ph; R1 = CO2Et, R2 = CH2CO2Et) to selectively form the Delta4-1,2,4-oxadiazoline complexes trans-[PtX2(PhCN) (N=C(Ph)-O-N(Me)-CR1R2)] or trans-[PtX2(N=C(Ph)-O-N(Me)-CR1R2)2] in high yields. The reactivity of the mixed ligand complexes trans-[PtX2(PhCN)(N=C(Ph)-O-N(Me)-CR1R2)] towards oxidation and ligand substitution was studied in more detail. Oxidation with Cl2 or Br2 provides the Pt(IV) species trans-[PtX2Y2(PhCN)(N=C(Ph)-O-N(Me)-CH(Ph))] (X, Y = Cl, Br). The mixed halide complex (X = Cl, Y = Br) undergoes halide scrambling in solution to form trans-[PtX(4-n)Yn(PhCN)(N=C(Ph)-O-N(Me)-CH(Ph))] as a statistical mixture. Ligand substitution in trans-[PtCl2(PhCN)(N=C(Ph)-O-N(Me)-CR1R2)] allows for selective replacement of the coordinated nitrile by nitrogen heterocycles such as pyridine, DMAP or 1-benzyl-2-methylimidazole to produce mixed ligand Pt(II) complexes of the type trans- [PtX2(heterocycle)(N=C(Ph)-O-N(Me)-CR1R2)]. All compounds were characterised by elemental analysis, mass spectrometry, IR and 1H, 13C and 195Pt NMR spectroscopy. Single-crystal X-ray structural analysis of (R,S)-trans-[PtBr2(N=C(Ph)-O-N(Me)-CH(Ph))2] and trans-[PtCl2(C5H5N)(N=C(Ph)-O-N(Me)-CH(Ph))] confirms the molecular structure and the trans configuration of the heterocycles relative to each other. 相似文献
6.
Xiao Yan Yafei Luo Xin Sun Wei Zhuo Jinke Gu Ke Zuo Xiaojun Gou Dianyong Tang Hubing Shi Wei Liu Jianping Hu 《应用有机金属化学》2019,33(10)
Designing deep‐blue phosphorescent materials is vital and essential in the construction of white organic light‐emitting diodes. Using density functional theory (DFT) and time‐dependent DFT, three tetradentate Pt(II) complexes were investigated in detail to reveal the influence of azole ligand with varying number of N atoms on the emission wavelengths and radiative and non‐radiative decay processes. The calculated results indicate that with an increase of N atoms in azole rings, the radiative decay process can be effectively facilitated. Moreover, an increase of N atoms in azole rings could lead to a distinct blue‐shift of emission wavelengths from 553 to 470 nm. Also, the non‐radiative decay processes, including temperature‐independent and temperature‐dependent ones, were taken into account. The results may provide some valuable and meaningful information for designing high‐performance phosphorescent Pt(II) complexes. 相似文献
7.
Summary Paramagnetic [OsIIIDQ2]+ and diamagnetic [OsIIAQ2] (Q = deprotonated 8-quinolinols, D = diimines and A = azoimines) complexes were prepared and characterised by physicochemical, magnetic and spectroscopic methods. The complexes exhibit several spin-allowed and spinforbidden charge-transfer transitions in the visible region. In MeCN solution the OsN4O2 unit displays nearly reversible OsIV-OsIII and OsIII-OsII couples in the ca. -0.4 to +1.1 V range versus SCE. An anodic shift of these responses is seen in going from diimines to azoimines. The stability of metal oxidation levels is correlated on the basis of -acceptor properties of these ligands. 相似文献
8.
Summary Mixed-ligand complexes formed by reaction of Cu(ClO4)2 with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (dppt) as primary ligand and 2,2-bipyridine (bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (dmp), N,N-bis(pyrid-2-ylmethyl)amine (dipica), N,N-bis(benzimidazol-2-ylmethyl)amine (bba), 1,3-bis(2-benzimidazolyl)-2-thiapropane (bbms) and 1,5-bis(benzimidazolyl)-3-thiapentane (bbes) as the secondary ligands have been isolated. They are of the type [Cu(dppt)L](ClO4)2·nH2O, where n = 0 or 2. All complexes exhibit only one ligand field band and their cryogenic solution e.p.r. spectra are axial, with vmax and g
values diagnostic of a square-based geometry. The spectral and redox data are consistent with facial coordination of the tridentate ligands. All the complexes exhibit a positive redox potential (versus n.h.e.). The weak -bonding of dppt, caused by the highly electron-withdrawing phenyl rings, the strong -back bonding involving phen and dmp, and interligand repulsions appear to be responsible for the relatively positive CuII/CuI redox potentials. 相似文献
9.
Pranab R. Basudhar Sutapa Sinha Pradyut K. Das Barindra K. Ghosh 《Transition Metal Chemistry》1996,21(2):154-157
Summary A group of mixed-tris chelates of type [OsAQ2] [A = isonitrosoacetophenonate (A1) and isonitroso-propiophenonate (A2); Q = deprotonated 8-quinolinol (Q1) and 2-methyl-8-quinolinol (Q2)] have been prepared by two distinct synthetic approaches. [OsAQ2]+, obtained by CeIV oxidation of [OsAQ2], can be regenerated by hydrazine hydrate reduction of the former. The complexes, characterized by physico-chemical, magnetic and spectroscopic methods, exhibit several spin-allowed and spin-forbidden charge transfer transitions in their electronic spectra. In MeCN solution the OsN3O3 unit displays a nearly-reversible OsIV-OsIII change and an OsIII-OsII couple in the ca. -1.0– + 0.3V range versus s.c.e. The stability of the metal oxidation levels is discussed in terms of the chemical and electrochemical results. 相似文献
10.
11.
Zrig S Koeckelberghs G Verbiest T Andrioletti B Rose E Persoons A Asselberghs I Clays K 《The Journal of organic chemistry》2007,72(15):5855-5858
The synthesis of a new series of Lambda-type, D-Pi-A regioregular oligothiophenes is described. The simultaneous presence of the chiral centers and the Lambda-type structure disfavored the formation of centro-symmetrical dimeric assemblies. Hence, enhanced first hyperpolarizabilities betaHRS were measured in comparison with those of the corresponding monomers. 相似文献
12.
M. Sivasankaran Nair P. Thillai Arasu M. Sankaranarayana Pillai C. Natarajan 《Transition Metal Chemistry》1995,20(2):132-135
Summary Stability constants for mixed-ligand complexes of the types [NiABH2], [NiABH] and [NiAB] formed by NiII with l-cysteine (cys), d-penicillamine (pen) or l-cysteic acid (cya) as ligand A and dl-2,3-diaminopropionic acid (dapa), dl-2,4-diaminobutyric acid (daba) or dl-ornithine (orn) as ligand B have been determined by the computerbased analysis of pH titration data obtained at 37 °C and I = 0.15 mol dm–3 (NaClO4). In the [NiABH] species, for all three secondary ligands (B), when A = pen or cya the labile proton appears to be attached to the terminal amino group of ligand B, whereas when A = cys it is not clear where the proton is located. In all the systems in the [NiABH2] species, one proton resides with the primary ligand (A) and the other with the secondary ligand (B). In the [NiAB]-type complexes, cys and pen chelate through the amino and thiolato groups, while cya binds in a glycine-like mode and the secondary ligands (B) coordinate in a terdentate manner.Author to whom all correspondence should be directed. 相似文献
13.
Tyler H. Struzinski Lydia R. von Gohren Amy H. Roy MacArthur 《Transition Metal Chemistry》2009,34(6):637-640
Four known electronically diverse cobalt(II) acetylacetonate derivatives were synthesized by replacement of the acetylacetonate
methyl groups with combinations of tert-butyl, ethoxy, and trifluoromethyl groups in order to study the effect of catalyst electronic properties on the reaction
rate and product yield of the cobalt-catalyzed reaction between haloalkenes and butylzinc iodide. Infrared spectroscopy of
these compounds showed an increase in the CO stretching frequency as the ligand substituents became more electron withdrawing.
These compounds, in addition to cobalt(II) acetylacetonate itself, were evaluated as catalysts for the coupling reaction between
(E)-1-iodo-1-octene and butylzinc iodide to form (E)-5-dodecene. Faster reaction rates were observed and higher yields of 5-dodecene were produced when catalysts containing
electron-donating ligands were employed. Side reactions, including the homocoupling of 1-iodo-1-octene to produce 7,9-hexadecadiene,
were also observed under the reported reaction conditions. The rate of side-product formation was more competitive with the
rate of the cross-coupling reaction when slower, electron-deficient catalysts were employed. 相似文献
14.
Grant GJ 《Dalton transactions (Cambridge, England : 2003)》2012,41(29):8745-8761
Platinum(II) and palladium(II) complexes of the trithiacrown [9]aneS(3) containing a range of Group 15 donors are reviewed. These complexes have the general formula [M([9]aneS(3))(L(2))](n+) where L represents at least one Group 15 donor. Complexes involving pnictogens, with the exception of bismuth, are observed. The complexes generally have an elongated square pyramidal geometry with a long distance interaction to the third sulphur of the [9]aneS(3) which forms the apex of the square pyramid. This axial metal-sulphur distance is quite sensitive to the donor properties of L. Poorer donors such as Sb and As ligands show short axial distances whereas the better N donor ligands show longer distances. Pt(II) complexes of the formula [Pt([9]aneS(3))(EPh(3))(2)](2+) (E = P, As, Sb) show a considerable distortion towards a trigonal bipyramidal geometry due to intramolecular π-π interactions. Over seventy of these types of complexes have been crystallographically characterized and are discussed in this article. Other unique features of the complexes, including NMR spectroscopy, redox chemistry, and electronic spectroscopy, are also discussed. 相似文献
15.
Curreli S Deplano P Faulmann C Ienco A Mealli C Mercuri ML Pilia L Pintus G Serpe A Trogu EF 《Inorganic chemistry》2004,43(16):5069-5079
The paper presents a detailed experimental and theoretical study of the four mixed nickel-bisdithiolene complexes [Ni(Pr(i)(2)pipdt)(dmit)] (1b, Pr(i)(2)pipdt = 1,4-diisopropyl-piperazine-3,2-dithione; dmit = 1,3-dithiolo-2-tione-4,5-dithiolato), [Ni(R(2)pipdt)(mnt)] (2b", R = 2-ethylhexyl; mnt = maleonitriledithiolato), [Ni(Pr(i)(2)timdt)(dmit)] (3b, Pr(i)(2)timdt = 1,3-diisopropyl-imidazoline-2,4,5-trithione), and [Ni(Pr(i)(2)timdt)(mnt)] (4b), and their models. All the complexes, with common (C(2)S(2))Ni(C(2)S(2)) core and two different terminal groups, are uncharged and square-planar coordinated. Previous measurements of the first molecular hyperpolarizability indicated that some of the species are potential NLO chromophores due to the pi-delocalized character of two frontier levels (HOMO and LUMO) which is asymmetrically perturbed by the combination of one push (R(2)pipdt, R(2)timdt) with one pull ligand (dmit and mnt). The X-ray structure of complex 1b is presented and its geometry is compared with those available in the literature for the four types of complexes under study. The results of electrochemical and spectroscopic measurements (oxidation and reduction potentials, IR, dipole moment, molecular absorptivities, etc.) indicate rather different responses between the pairs of complexes 1-2 and 3-4. Hence, DFT calculations on the model compounds 1a-4a, where hydrogen atoms replace the alkyl groups of R(2)pipdt and R(2)timdt, have been carried out to correlate geometries and electronic structures. Moreover, the first molecular hyperpolarizabilities have been calculated and their components have been analyzed with the simplest two-level approximation. The derived picture highlights the different roles of the two push and pull ligands, but also the peculiar perturbation of the pi-electron density induced by the terminal CS(3) grouping of the ligand dmit. 相似文献
16.
There have been synthesized Pt(II) stereoisomeric complexes with hydroxy-α-amino acid serine (SerH = NH2CH(CH2OH)COOH is α-amino-β-hydroxypropionic acid): trans-[Pt(S-SerH)2Cl2], trans-[Pt(R-SerH)(S-SerH)Cl2] with monodentately (through NH2 group ) bound SerH and cis-, trans-[Pt(R-Ser)(S-Ser)], trans-[Pt(S-Ser)2] with bidentately bound (through groups NH2 and COO) ligands (R, S is the absolute configuration of asymmetric carbon atom). The successive phases in the synthesis of Pt(II) stereoisomeric complexes with serine were studied by 195Pt NMR spectroscopy. To identificate the compounds synthesized the method of elemental analysis, IR and NMR (195Pt, 13C, 1H) spectroscopy were used. For trans-[Pt(R-Ser)(S-Ser)] the X-ray diffraction data were obtained. 相似文献
17.
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19.
Complexes of tetradentate macrocyclic Schiff base ligand, L, with MnII and PdII ions have been synthesized by the template condensation of 1,10-phenanthroline-2, 9-dicarboxaldehyde, 2,3-diamino-1,4-naphthoquinone and 1,2-dibromoethane in EtOH. The complexes were characterized by physicochemical and spectroscopic methods and an octahedral geometry is suggested for their structure. They have been screened for antibacterial activity against several bacteria, and the results are compared with the activity of penicillin. 相似文献
20.
Vicente J Chicote MT Guerrero R Vicente-Hernandez I Jones PG Bautista D 《Inorganic chemistry》2006,45(13):5201-5209
The reactions of [Ag(NH=CMe2)2]ClO4 with cis-[PtCl2L2] in a 1:1 molar ratio give cis-[PtCl(NH=CMe2)(PPh3)2]ClO4 (1cis) or cis-[PtCl(NH=CMe2)2(dmso)]ClO4 (2), and in 2:1 molar ratio, they produce [Pt(NH=CMe2)2L2](ClO4)2 [L = PPh3 (3), L2= tbbpy = 4,4'-di-tert-butyl-2,2'-dipyridyl (4)]. Complex 2 reacts with PPh3 (1:2) to give trans-[PtCl(NH=CMe2)(PPh3)2]ClO(4) (1trans). The two-step reaction of cis-[PtCl2(dmso)2], [Au(NH=CMe2)(PPh3)]ClO4, and PPh3 (1:1:1) gives [SP-4-3]-[PtCl(NH=CMe2)(dmso)(PPh3)]ClO4 (5). The reactions of complexes 2 and 4 with PhICl2 give the Pt(IV) derivatives [OC-6-13]-[PtCl3(NH=CMe2)(2)(dmso)]ClO4 (6) and [OC-6-13]-[PtCl2(NH=CMe2)2(dtbbpy)](ClO4)2 (7), respectively. Complexes 1cis and 1trans react with NaH and [AuCl(PPh3)] (1:10:1.2) to give cis- and trans-[PtCl{mu-N(AuPPh3)=CMe2}(PPh3)2]ClO4 (8cis and 8trans), respectively. The crystal structures of 4.0.5Et2O.0.5Me2CO and 6 have been determined; both exhibit pseudosymmetry. 相似文献