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1.
Igarashi S  Suzuki H  Yotsuyanagi T 《Talanta》1995,42(8):1171-1177
The equilibrium constants of alpha,beta,gamma,delta-tetrakis(1-methylpyridinium-4-yl)porphine (TMPyP) complexes of cadmium(II), lead(II), magnesium(II), and zinc(II) were spectrophotometrically determined using the absorption spectra at the Soret band and the fluorescence spectra. The values of the following constants at 25 degrees C and ionic strength 0.1M were evaluated: K(PbP) = 10(-8.07 +/- 0.09), K(CdP) = 10(-7.68 +/- 0.03), K(ZnP) = 10(1.72 +/- 0.08), and K(MgP) = 10(-7.40 +/- 0.08) by the acid hydrolysis reaction of the TMPyP-metal complex at various pHs; K(PbP) = 10(-7.80 +/- 0.04) and K(CdP) = 10(-7.38 +/- 0.04) were determined by the ligand exchange reaction between TMPyP and nitrilotriacetic acid.  相似文献   

2.
The crystal field effect and microscopic origins of the Zeeman g-factors g(//) and g(⊥) for (6)S(3d(5)) state ions at tetragonal symmetry crystal filed, taking into account the spin-spin (SS), the spin-other-orbit (SOO), and the orbit-orbit (OO) magnetic interactions besides the well-known spin-orbit (SO) magnetic interaction, have been investigated using the microscopic spin Hamiltonian theory and the complete diagonalization method (CDM). It is found that the g(//)(±1/2)≠g(//)(±5/2) and g(⊥)(±1/2)≠g(⊥)(±5/2), where the g-factors g(//)(±1/2) and g(⊥)(±1/2) express the g-factors of the ground state |M?(s)=±1/2), whereas the g-factors g(//)(±5/2) and g(⊥)(±5/2) express the g-factors of the ground state |M?(s)=±5/2). It is shown that although the SO magnetic interaction is the most important one, the contributions to the shifts of g-factors Δg(//)(=2.0023-g(//)) and Δg(⊥)(=2.0023-g(⊥)) from other three magnetic interactions including the SS, SOO, and OO magnetic interactions are appreciable and should not be omitted, especially for the shifts of g-factors Δg(//)(±5/2) and Δg(⊥)(±5/2). The individual contributions to the shifts of g-factors arising from the spin quartet states and spin doublet states have been studied. The investigations show that the Δg(//)(±1/2) and Δg(⊥)(±1/2) primarily result from the spin quartet states, whereas Δg(//)(±5/2) and Δg(⊥)(±5/2) from the spin quartet states as well as the combined effects between the spin quartet states and the spin doublet states. The contribution to the shifts of g-factors from the net spin doublet states is zero.  相似文献   

3.
<正> Mr=448.5, monoclinic P21/c, a=8.531(3), B=12.076(4), C=33.309(13) A, β=95.41(1)°, V=3416.2(2) A3, Z=4, μ(MoKα)= 1.2 cm-1, F(000)=1408, room temperature, R=0.086, Rw=0.084 (W=1/(σ2(F) + 0.0001 x F2)) for 1759 independent reflections with I > 3σ(I).  相似文献   

4.
FENG Fu 《结构化学》2010,29(12):1760-1763
A novel compound of 9-[3-oxo-1-(4-bromopheny)-3-phenypropyl]fluorine (3) was synthesized via nucleophilic addition reaction under solvent-free condition. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of triclinic system, space group P-1 with a=9.7919(16), b=11.0932(18), c=11.2534(19) , α=76.927(3), β=67.452(3), γ=84.895(3)°, V=1099.7(3) 3, Z=2, Dc=1.369 g/cm3, μ=1.886 mm-1, F(000)=464, R=0.0586 and wR=0.1562 for 3145 observed reflections with Ⅰ 2σ(Ⅰ). π-π Stacking interactions contribute to the stability of the structure.  相似文献   

5.
The title compound (C14H12N2O2,Mr=240.26) crystallizes in the monoclinic system,space group P21/a with a=7.394(1),b=21.334(3),c=7.423(1)A,β=89.82(1)A°,V=1170.8(3)A3,Z=4,Dc=1.363 g/cm3,μ(MoKα)=0.93 cm-1 and F(000)=504.00.The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I>2σ(I)),respectively.The dihedral angle between the two phenyl rings is 52.9°and that between the NO2 group and its attached ring is 3.0°.In the crystal,molecules are stacked along [100] throughπ…πinteractions.The C-H…O hydrogen bond (3.403 A,120.4°) laterally connects the stacks along [010] to form networks (001) which are further anti-parallelly connected by C-H…O(3.382 A,142.9°) andπ…πinteractions extending along [001].Also presented here is a brief study on the C-H…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types,namely,R12(5)R21(4),R22(8),R12(6),andR22(7),with the first three occurring more often.  相似文献   

6.
A new tripodal P,N ligand (C63H48N3O3P3) was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 13.013(3), b = 28.406(6), c = 14.911(3) A^°, β= 111.04(3)°, V= 5144.6(18) A^°^3 Z = 4, Dc = 1.276 g/cm^3, Mr = 987.95, λ(MoKa) = 0.71073 A^°,μ = 0.17 mm^-1, F(000) = 2064, R = 0.0786 and wR = 0.1545. A total of 43260 unique reflections were collected, of which 5112 with I 〉 2σ(I) were observed. The title compound has a central benzene ring, which is linked by -NH-CO- bonds to three 2-aminophenyltriphenylphosphium moieties, of which two with P(1) and P(2) centers are pointing to the same face of the central aryl ring, while the third one directs oppositely, forming a pseudo-propeller. In the crystal structure, there exist face-to-face π-π stacking interactions which increase the stability of the crystal structure.  相似文献   

7.
用X-射线晶体结构衍射测定了吲哚醌缩吉拉尔特试剂T(C13H18N4O2Cl)的晶体结构。该晶体属单斜晶系,空间群P21/n, a =12.250(2),b = 13.631(2), c = 9.777(1) ?,β= 113.506(7) °,V =1497.1(4) ?3,Mr =297.76,Dc =1.321g/cm3,m =2.6cm-1,F(000)=628,Z =4,R =0.0715,wR =0.1843, (I>2σ(I))。晶体结构呈蝎形,由于空间位阻的影响,该配体很难与金属离子形成配合物。  相似文献   

8.
The absolute cross sections (CSs) for electronic excitations of cytosine by electron impact between 5 and 18 eV were measured by electron-energy-loss (EEL) spectroscopy of the molecule deposited at low coverage on an inert Ar substrate. The lowest EEL features found at 3.55 and 4.02 eV are ascribed to transitions from the ground state to the two lowest triplet 1?(3)A(')(π→π(?)) and 2?(3)A(')(π→π(?)) valence states of the molecule. Their energy dependent CSs exhibit essentially a common maximum at about 6 eV with a value of 1.84×10(-17)?cm(2) for the former and 4.94×10(-17)?cm(2) for the latter. In contrast, the CS for the next EEL feature at 4.65 eV, which is ascribed to the optically allowed transition to the 2?(1)A(')(π→π(?)) valence state, shows only a steep rise to about 1.04×10(-16)?cm(2) followed by a monotonous decrease with the incident electron energy. The higher EEL features at 5.39, 6.18, 6.83, and 7.55 eV are assigned to the excitations of the 3?(3,1)A(')(π→π(?)), 4?(1)A(')(π→π(?)), 5?(1)A(')(π→π(?)), and 6?(1)A(')(π→π(?)) valence states, respectively. The CSs for the 3?(3,1)A(') and 4?(1)A(') states exhibit a common enhancement at about 10 eV superimposed on a more or less a steep rise, reaching, respectively, a maximum of 1.27 and 1.79×10(-16)?cm(2), followed by a monotonous decrease. This latter enhancement and the maximum seen at about 6 eV in the lowest triplet states correspond to the core-excited electron resonances that have been found by dissociative electron attachment experiments with cytosine in the gas phase. The weak EEL feature found at 5.01 eV with a maximum CS of 3.8×10(-18)?cm(2) near its excitation threshold is attributed to transitions from the ground state to the 1?(3,1)A(")(n→π(?)) states. The monotonous rise of the EEL signal above 8 eV is attributed to the ionization of the molecule. It is partitioned into four excitation energy regions at about 8.55, 9.21, 9.83, and 11.53 eV, which correspond closely to the ionization energies of the four highest occupied molecular orbitals of cytosine. The sum of the ionization CS for these four excitation regions reaches a maximum of 8.1×10(-16)?cm(2) at the incident energy of 13 eV.  相似文献   

9.
The optical transitions of supersonically cooled OsN have been investigated in the range from 19,200 to 23,900 cm(-1) using resonant two-photon ionization spectroscopy. More than 20 vibronic bands were observed, 17 of which were rotationally resolved and analyzed. The ground state is confirmed to be (2)Δ(5/2), deriving from the 1σ(2) 2σ(2) 1π(4) 1δ(3) 3σ(2) electronic configuration. The X (2)Δ(5/2) ground state rotational constant for (192)Os(14)N was found to be B(0) = 0.491921(34) cm(-1), giving r(0) = 1.62042(6) ? (1σ error limits). The observed bands were grouped into three band systems with Ω' = 7/2 and four with Ω' = 3/2, corresponding to the three (2)Φ(7/2) and four (2)Π(3/2) states expected from the 1σ(2) 2σ(2) 1π(4) 1δ(3) 3σ(1) 2π(1) and 1σ(2) 2σ(2) 1π(4) 1δ(2) 3σ(2) 2π(1) electronic configurations. In addition, two interacting upper states with Ω' = 5/2 were observed, one of which is thought to correspond to a 1σ(2) 2σ(2) 1π(3) 1δ(3) 3σ(2) 2π(1), (2)Δ(5/2) state. Spectroscopic constants are reported for all of the observed states, and comparisons to related molecules are made. The ionization energy of OsN is estimated as IE(OsN) = 8.80 ± 0.06 eV.  相似文献   

10.
1 INTRODUCTION A new class of materials of metal oxide clusters based on anionic molybdenum phosphate frameworks has received much attention as a consequence of their potential applications in catalysis and materials science [1]. As a result, some molybdenum phosphates have been studied [2,3]. Recently we have studied the structure of NaPMO material[4] and the spectrum of multicomponent compound with Keggin struc- ture [5]. Here we report the synthesis and crystal structure of a new…  相似文献   

11.
1 INTRODUCTIONInrecentyears,therehasbeenmuchinterestinphosphoranescontainingonlyonephosphorus-phosphorusbondandthestructuresofmostofthesecompoundshavebeenidentifiedbyX-raycrystallography[1~6].In1990,anewtypeofphosphoraneinvolvingtwoP-Pbondswassuccessfullysynthesized[7],butthecrystalstructurewasnotdetermined.Wehavesuccessfullysynthesizedthenovelphosphorane3bear-ingthreeP-Pbonds.Hereitscrystalstructureisreported.2 EXPERIMENTAL2.1 PreparationAllprocedureswereperformedunderN2atmos…  相似文献   

12.
1 INTRODUCTION3methyl4hydroxybenzofuranisanintermediateusedforthesynthesisofnatureproducts[1].Ithasbeensynthesizedfrom1,3dihydroxybenzene[2-3].Tosynthesizeabietanequinonediterpenoidswithit[4,5],weintendedtoprotectthehydroxyattachedtoitwithMe2SO4.Finally,twocompou…  相似文献   

13.
A mercury(Ⅱ) iodide complex with organosulfide [Hg(pymt)(pymtH)I] 1 (pymt = the anion of pyrimidine-2-thiolate) has been synthesized by slow evaporation of the solution at room temperature and structurally characterized by single-crystal X-ray diffraction. Basic ideas and data collected are given. X-ray diffraction analysis reveals that complex 1 is mononuclear. Crystallographic data: C8H7HgIN4S2, Mr = 550.79, monoclinic system, space group P21/c, a = 11.218(4), b = 9.551(3), c = 15.877(4) A^°, β = 129.697(15)°, V = 1308.9(7) A^°^3, Z = 4, Mr = 550.79, Dc = 2.795 g/cm^3, F(000) = 995, μ(MoKa) = 14.415 mm^-1, 2(MoKa) = 0.71073 A^°, T= 293(2) K, 2θmax = 54.9°, GOOF= 1.053, the final R = 0.0310 and wR = 0.0742 for 2547 observed reflections with I 〉 2σ(I) (refinement on F^2). Complex 1 is connected through hydrogen bonds to give a one-dimensional supramolecular chain structure. Furthermore, π-π interactions are also found between the pyrimidine rings with the center-to-center distances of 3.439(4) and 3.603(4) A^°, so complex 1 expands the chains into a two-dimensional network.  相似文献   

14.
One new organic adduct,isonicotinamide·3,5-dinitrosalicylic acid with isonico-tin-amide(ina) and 3,5-dinitrosalicylic acid(3,5-dnsa) in 1:1 molar ratio,has been synthesized.Its struc-ture(C13H10N4O8,Mr = 350.25) was characterized by elemental analysis,IR and single-crystal X-ray diffraction analysis.The crystal belongs to the triclinic system,space group P1,with a = 8.812(4),b = 9.487(5),c = 9.604(6) ,α = 116.54(2),β = 97.29(5),γ = 98.35(4)°,V = 693.8(7) 3,Z = 2,Dc = 1.677 g/cm3,λ(MoKα) = 0.71073 ,μ = 0.142 mm-1,F(000) = 360,the final R = 0.0539 and wR = 0.1402 for 2417 unique reflections(Rint = 0.0288) with 1819 observed ones(Ⅰ 2σ(Ⅰ)).Proton transfer reaction occurs between 3,5-dnsa and ina molecules,and the hydrogen bonds(N-H…O and C-H…O) with other interactions(π…π stacking and weak interactions of O…O and C…O) cooperatively construct a three-dimensional(3D) supramolecular structure.  相似文献   

15.
1 INTRODUCTIONInordertoevaluatetheselectivityandreactivityofenonesasdienonephilesanddienesinDielsAlderreaction,Paraltasynthesizedβfunctionalizedlacetylvinylarenecarboxylatesasasubstrateof1,3dipolarcycloaddionreaction〔1〕.Xraycrystallographicstud…  相似文献   

16.
以Co(ClO4)2·6H2O/Cu(ClO4)2·6H2O、1,4-双(咪唑基-1-基)丁烷(bib)/1,4-双(咪唑基-1-基)苯(bix)和4,4-(1,3-苯基双(亚甲基氧基))二苯甲酸(H2pmda)为原料,在水热条件下反应,得到了2个配合物{[Co(bib)3](ClO4)2}n(1)和{[Cu3(bix)(4.5)](ClO4)3}n(2)(H2pmda未参与反应),对它们进行了元素分析、红外光谱、荧光光谱、单晶和粉末X射线衍射表征。配合物1属于三方晶系,R 空间群,a=b=1.39337(5)nm,c=1.74054(13)nm,V=2.9265(3)nm^3,Mr=828.59,Dc=1.410g·cm^-3,F(000)=1293,μ=0.639mm^-1,Z=3,R1=0.0611,wR2=0.1937(I>(2σ(I))。配合物2也属于三方晶系,P 空间群,a=b=2.33441(15)nm,c=0.71511(9)nm,V=3.3749(5)nm^3,Mr=1561.28,Dc=1.536g·cm^-3,F(000)=1602,μ=1.131mm^-1,Z=2,R1=0.0439,wR2=0.1090(I>(2σ(I))。单晶结构分析表明配合物1为含有36元环的二维网状结构,配合物2为含有84元环的二维网状结构,并通过氢键或π-π堆积使它们扩展成超分子结构。此外,还研究了2个配合物的荧光性质。  相似文献   

17.
1mTRODUCTIONAzamacrocyclicligandsandtheirmacrocyclicderivativeswithincorporatingpendantarmsgroupshavereceivedmuchattentionfortheirusesiniontransportandasmodelsinbiomimicresearchc1-51.Recentlymuchattentionisespeciallyfocusedonstudyingtransitionmetalcomplexesofmacrocycles"-".Conversely,onlyafewre-Portsareaboutcomplexesofmixedoxygen-nitrogendonormacrocyclesincorporatingtwoPendantarms,mostofwhicharecarboxylicacidgroups.Theymaybeappliedinionidentification,iontransportandionseparation"-"'aswell…  相似文献   

18.
1 INTRODUCTION Procedures to synthesize copper(I) complexes are of great interest because of the diversity of products resulting from almost the same methodology. It has long been known that four-electron-donor diphosphine compounds Ph2P(CH2)nPPh2 are excellent bidentate ligands[1]. The chelating tendency decreases as the chain length increases, so that for the ligands Ph2P(CH2)nPPh2, the tendency to chelation is the greatest for bis(diphenylphosphino)ethane. Copper(I) displays wide…  相似文献   

19.
The first solid-state NMR investigation of dichalcogenoimidodiphosphinato complexes, M[N(R(2)PE)(2)](n), is presented. The single-source precursors for metal-selenide materials, M[N((i)Pr(2)PSe)(2)](2) (M = Zn, Cd, Hg), were studied by solid-state (31)P, (77)Se, (113)Cd, and (199)Hg NMR at 4.7, 7.0, and 11.7 T, representing the only (77)Se NMR measurements, and in the case of Cd[N((i)Pr(2)PSe)(2)](2)(113)Cd NMR measurements, to have been performed on these complexes. Residual dipolar coupling between (14)N and (31)P was observed in solid-state (31)P NMR spectra at 4.7 and 7.0 T yielding average values of R((31)P,(14)N)(eff) = 880 Hz, C(Q)((14)N) = 3.0 MHz, (1)J((31)P,(14)N)(iso) = 15 Hz, alpha = 90 degrees , beta = 26 degrees . The solid-state NMR spectra obtained were used to determine the respective phosphorus, selenium, cadmium, and mercury chemical shift tensors along with the indirect spin-spin coupling constants: (1)J((77)Se,(31)P)(iso), (1)J((111/113)Cd,(77)Se)(iso), (1)J((199)Hg,(77)Se)(iso), and (2)J((199)Hg,(31)P)(iso). Density functional theory magnetic shielding tensor calculations were performed yielding the orientations of the corresponding chemical shift tensors. For this series of complexes the phosphorus magnetic shielding tensors are essentially identical, the selenium magnetic shielding tensors are also very similar with respect to each other, and the magnetic shielding tensors of the central metals, cadmium and mercury, display near axial symmetry demonstrating an expected deviation from local S(4) symmetry.  相似文献   

20.
Isolation and Crystal Structure of Horminone   总被引:1,自引:0,他引:1  
1 INTRODUCTIONhorminoneRabdsia serra( Maxim) hara,a tradi-tional Chinese medicine for the treatmentofhepatitis,enteritis,acute cholecystitis anddysentery,is a perennial herb distributedmainly in central and southeastern parts ofChina〔1〕.In previous reports,four diter-penoids,Rabdoserrin A,Rabdoserrin B,Excisanin A and Kamebakaurin which be-long to ent- kaurene diterpenoids have beenisolated from this source〔2 ,3〕.Horminonewhich has the structure of abietane quinonewas once isolate…  相似文献   

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