OCS+经由A2П←X2П激发的光解离光谱

在超声分子束条件下,由423、420、412.2和408.4nm的电离激光使OCS分子通过[3+1]共振增强多光子电离(REMPI)制备出OCS+(X2Π)离子后,在260-325nm范围内扫描解离激光获得了OCS+离子经由A2Π3/2←X2Π3/2(000)和A2Π1/2←X2Π1/2(000,001)跃迁的分质量光解离谱(母体离子OCS+的凹陷谱和碎片离子S+的增强谱).其中A2Π1/2←X2Π1/2(001)跃迁的光解离谱是首次观察到.由A2Π3/2←X2Π3/2(000)光解离谱得到了A2Π3/2电子态的光谱常数T0=31411.3cm-1,ν1=814.3cm-1;由A2Π1/2←X2Π1/2(000)光解离谱得到了A2Π1/2电子态的光谱常数ν1=816cm-1,ν2=(380.4±2.8)cm-1,ν3=(2052.7±5.1)cm-1,而从A2Π1/2←X2Π1/2(001)光解离谱拟合出的A2Π1/2电子态的ν1(786.4cm-1)稍有不同,表明在A2Π1/2←X2Π1/2(001)跃迁中X2П1/2电子态的C-O键振动(ν3)激发影响了A2Π1/2电子态C-S键的振动(ν1).实验结果表明:在A2Π1/2←X2Π1/2(000,001)跃迁的光解离谱中能够显著观察到属于A2Π电子态的ν2弯曲振动模激发的谱峰,例如A2Π1/2(020,120,021,…),而在A2П3/2(υ1υ2υ3)←X2Π3/2(000)跃迁的光解离谱中几乎没有观察到属于ν2弯曲振动模激发的谱峰.这种弯曲振动激发和A2П电子态的旋轨分裂分量(Ω)的相关性可以通过A2Π电子态的Fermi共振和Renner-Teller效应来解释.     

Ab initio calculations on low-lying electronic states of SbO2- and Franck-Condon simulation of its photodetachment spectrum

Geometry optimization and harmonic vibrational frequency calculations have been carried out on the low-lying singlet and triplet electronic states of the antimony dioxide anion (SbO2-) employing a variety of ab initio methods. Both large-core and small-core relativistic effective core potentials were used for Sb in these calculations, together with valence basis sets of up to augmented correlation-consistent polarized-valence quintuple-zeta (aug-cc-pV5Z) quality. The ground electronic state of SbO2- is determined to be the X (1)A1 state, with the a (3)B1 state, calculated to be approximately 48 kcal mole(-1) (2.1 eV) higher in energy. Further calculations were performed on the X (2)A1, A (2)B2, and B (2)A2 states of SbO2 with the aim to simulating the photodetachment spectrum of SbO(2) (-). Potential energy functions (PEFs) of the X (1)A1 state of SbO2- and the X (2)A1, A (2)B2, and B (2)A2 states of SbO2 were computed at the complete-active-space self-consistent-field multireference internally contracted configuration interaction level with basis sets of augmented correlation-consistent polarized valence quadruple-zeta quality. Anharmonic vibrational wave functions obtained from these PEFs were used to compute Franck-Condon factors between the X (1)A1 state of SbO2- and the X (2)A1, A (2)B2, and B (2)A2 states of SbO2, which were then used to simulate the photodetachment spectrum of SbO2-, which is yet to be recorded experimentally.     

铽与1-苯基-3-甲基-4-酰代吡唑啉-5-酮的三元配合物的合成、表征与荧光性能

合成了铽与1-苯基-3-甲基-4-异丁酰基吡唑啉-5-酮(HPMIBP)、1-苯基-3-甲基-4-苯甲酰基吡唑啉-5-酮(HPMBP)的四个三元配合物Tb(PMIBP)3.2H2O(A1), Tb(PMIBP)3.bpy(A2), Tb(PMBP)3.2H2O(B1)和Tb(PMBP)3.bpy(B2)(bpy=2, 2'-联吡啶)。用元素分析确定了它们的组成, 并用紫外-可见光谱、红外光谱、差热-热重谱对其进行了表征。研究了它们在固态和溶液中的荧光光谱, 并用频域法测定了它们在溶液中的荧光寿命, 结果表明A1和A2的荧光强度比相应的B1和B2强三个数量级, A2与A1或B2与B1相比, 荧光强度也有一定程度的增强,并且不同溶剂对其荧光强度和荧光寿命都有较大的影响。     

Bromine-loss and hydrogen-loss dissociations in low-lying electronic states of the CH3Br+ ion studied using multiconfiguration second-order perturbation theory

Complete active space self-consistent field (CASSCF) and multiconfiguration second-order perturbation theory (CASPT2) calculations with an ANO-RCC basis were performed for the 1(2)A', 1(2)A", 2(2)A', and 2(2)A" states of the CH3Br+ ion. The 1(2)A' state is predicted to be the ground state. The 2(2)A' state is predicted to be a bound state. The adiabatic and vertical excitation energies and the relative energies at the molecular geometry were calculated, and the energetic results for 2(2)A' and 2(2)A" are in reasonable agreement with the experimental data. Potential energy curves (PECs) for Br-loss and H-loss dissociations from the four C(s) states were calculated at the CASPT2//CASSCF level and the electronic states of the CH3(+) and CH2Br(+) ions as the dissociation products were determined by checking the relative energies and geometries of the asymptote products along the PECs. In the Br-loss dissociation, the 1(2)A', 1(2)A", and 2(2)A' states correlate with CH3(+) (X1A1') and the 2(2)A" state correlates with CH3(+) (1(3)A"). The energy increases monotonically with the R(C-Br) value along the four Br-loss PECs. In the H-loss dissociation the 1(2)A', 1(2)A", 2(2)A', and 2(2)A" states correlate with the X(1)A(1), 1(3)A", 1(3)A', and 1(1)A" states (1(3)A' lying above 1(1)A") of CH2Br(+), respectively. Along the 2(2)A" H-loss PEC there is an energy barrier and the CASSCF wave functions at large R(C-H) values have shake-up ionization character. Along the 2(2)A' H-loss PEC there are an energy barrier and a minimum. At the end of the present paper we present a comprehensive review on the electronic states and the X-loss and H-loss dissociations of the CH(3)X(+) (X = F, Cl, and Br) ions on the basis of our previous studies and the present study.     

Cl-loss and H-loss dissociations in low-lying electronic states of the CH3Cl+ ion studied using multiconfiguration second-order perturbation theory

To examine the experimentally suggested scheme of the pathways for Cl- and H-loss dissociations of the CH(3)Cl(+) ion in the X(2)E (1(2)A', 1(2)A' '), A(2)A(1) (2(2)A'), and B(2)E (3(2)A', 2(2)A") states, the complete active space-self-consistent field (CASSCF) and multiconfiguration second-order perturbation theory (CASPT2) calculations with an atomic natural orbital (ANO) basis were performed for the 1(2)A' (X(2)A'), 1(2)A", 2(2)A', and 2(2)A'" states. The potential energy curves describing dissociation from the four C(s) states were obtained on the basis of the CASSCF partial geometry optimization calculations at fixed C-Cl or C-H distance values, followed by the CASPT2 energy calculations. The electronic states of the CH3(+) and CH(2)Cl(+) ions produced by Cl-loss and H-loss dissociation, respectively, were carefully determined. Our calculations confirm the following experimental facts: Cl-loss dissociation occurs from the 1(2)A' (X(2)A'), 1(2)A", and 2(2)A' states (all leading to CH3(+) (X(1)A(1)') + Cl), and H-loss dissociation does not occur from 2(2)A'. The calculations indicate that H-loss dissociation occurs from the 1(2)A' and 1(2)A' ' states (leading to CH(2)Cl(+) (X(1)A(1)) + H and CH(2)Cl(+) (1(3)A") + H, respectively). The calculations also indicate that H-loss dissociation occurs (with a barrier) from the 2(2)A" state (leading to CH(2)Cl(+) (1(1)A") + H), supporting the observation of direct dissociation from the B state to CH(2)Cl(+) and that Cl-loss dissociation occurs from the 2(2)A" state (leading to CH3(+) (1(3)A") + Cl), not supporting the previously proposed Cl-loss dissociation of the B state via internal conversion of B to A. The predicted appearance potential values for CH3(+) (X(1)A(1)') and CH(2)Cl(+) (X(1)A(1)) are in good agreement with the experimental values.     

Theoretical transition probabilities for the A 1Pi-X 1Sigma+ system of AlNC and AlCN isomers based on global potential energy surfaces

Transition probabilities were evaluated for the X (1)Sigma(+)-A (1)Pi system of AlNC and AlCN isomers to analyze photoabsorption and fluorescence spectra. The global potential energy surfaces (PESs) of the X (1)Sigma(+) and A (1)Pi (1 (1)A("),2 (1)A(')) electronic states were determined by the multireference configuration interaction calculations with the Davidson correction. Einstein's B coefficients were computed by quantum vibrational calculations using the three-dimensional PESs of these states and the electronic transition moments for the X-1 (1)A(") and X-2 (1)A(') systems. Einstein's B coefficients obtained for AlNC or AlCN exhibit that the Al-N or Al-C stretching mode is strongly enhanced in the transition. The absorption and fluorescence spectra calculated for the X-1 (1)A(") and X-2 (1)A(') systems are discussed comparing with the observed photoexcitation and fluorescence spectra. The lifetimes for the several vibrational levels of the A (1)Pi state were calculated to be ca. 7 ns for AlNC and 21-24 ns for AlCN from the fluorescence decay rates of the 1 (1)A(")-X and 2 (1)A(')-X emissions.     

New triterpenoid saponins from Maesa tenera.

Two new triterpenoid saponins, maetenosides A and B were isolated from the aerial parts of Maesa tenera and were respectively defined as 3-O-[beta-D-glucopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (1) and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-o-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (2). Their structures were established on the basis of chemical and spectroscopic methods.     

X, A, B, C, and D states of the C6H5F+ ion studied using multiconfiguration wave functions

Electronic states of the C6H5F+ ion have been studied within C2v symmetry by using the complete active space self-consistent field (CASSCF) and multiconfiguration second-order perturbation theory (CASPT2) methods in conjunction with an atomic natural orbital basis. Vertical excitation energies (Tv) and relative energies (Tv') at the ground-state geometry of the C6H5F molecule were calculated for 12 states. For the five lowest-lying states, 1(2)B1, 1(2)A2, 2(2)B1, 1(2)B2, and 1(2)A1, geometries and vibrational frequencies were calculated at the CASSCF level, and adiabatic excitation energies (T0) and potential energy curves (PEC) for F-loss dissociations were calculated at the CASPT2//CASSCF level. On the basis of the CASPT2 T0 calculations, we assign the X, A, B, C, and D states of the ion to 1(2)B1, 1(2)A2, 2(2)B1, 1(2)B2, and 1(2)A1, respectively, which supports the suggested assignment of the B state to (2)(2)B1 by Anand et al. based on their experiments. Our CASPT2 Tv and Tv' calculations and our MRCI T0, Tv, and Tv' calculations all indicate that the 2(2)B1 state of C6H5F+ lies below 1(2)B2. By checking the relative energies of the asymptote products and checking the fragmental geometries and the charge and spin density populations in the asymptote products along the CASPT2//CASSCF PECs, we conclude that the 1(2)B1, 1(2)B2, and 1(2)A1 states of C6H5F+ correlate with C6H5+ (1(1)A1) + F (2P) (the first dissociation limit). The energy increases monotonically along the 1(2)B1 PEC, and there are barriers and minima along the 1(2)B2 and 1(2)A1 PECs. The predicted appearance potential value for C6H5+ (1(1)A1) is very close to the average of the experimental values. Our CASPT2//CASSCF PEC calculations have led to the conclusion that the 1(2)A2 state of C6H5F+ correlates with the third dissociation limit of C6H5+ (1(1)A2) + F (2P), and a preliminary discussion is presented.     

含有羧基配体的蝎型钒氧配合物的合成、结构及其热分解动力学

设计合成了两种新型的以聚吡唑硼酸盐、氨基酸为配体的钒氧配合物VO[phCH2CH(NH2)COO][HB(pz)3](1)和VO(3,5-Me2pz)[HB(3,5-Me2pz)3](CH3COO)(2). 通过元素分析、红外光谱对配合物进行了表征, 并利用单晶X射线衍射技术解析了它们的结构. 非等温热分解动力学研究表明, 配合物1和2的热分解反应都是分两步进行的. 通过计算, 配合物1热分解的第一步反应的可能机理为成核与生长(n=1/4); 第二步反应的可能机理为化学反应. 其非等温动力学方程分别为, dα/dT=(A/β)e-E/RT(1/4)(1-α)[-ln(1-α)]-3 和dα/dT=(A/β)e-E/RT(1-α)2. 分解反应的表观活化能分别是223.52 和331.94 kJ·mol-1; 指前因子ln(A/s-1)分别是49.67 和57.50. 配合物2 热分解的第一步反应的可能机理为化学反应; 第二步反应的可能机理为成核与生长(n=1/2). 其非等温动力学方程分别为, dα/dT=(A/β)e-E/RT(1-α)2, 和dα/dT=(A/β)e-E/RT(1/2)(1-α)[-ln(1-α)]-1. 分解反应的表观活化能分别是300.56 和444.72 kJ·mol-1; 指前因子ln(A/s-1)分别是75.53 和92.50.     

The 1 (2)A(1), 1 (2)B(2), and 1 (2)A(2) states of the SO(2) (+) ion studied using multiconfiguration second-order perturbation theory

The 1 (2)A(1), 1 (2)B(2), and 1 (2)A(2) electronic states of the SO(2) (+) ion have been studied using multiconfiguration second-order perturbation theory (CASPT2) and two contracted atomic natural orbital basis sets, S[6s4p3d1f]/O[5s3p2d1f] (ANO-L) and S[4s3p2d]/O[3s2p1d] (ANO-S), and the three states were considered to correspond to the observed X, B, and A states, respectively, in the previous experimental and theoretical studies. Based on the CASPT2/ANO-L adiabatic excitation energy calculations, the X, A, and B states of SO(2) (+) are assigned to 1 (2)A(1), 1 (2)B(2), and 1 (2)A(2), respectively, and our assignments of the A and B states are contrary to the previous assignments (A to (2)A(2) and B to (2)B(2)). The CASPT2/ANO-L energetic calculations also indicate that the 1 (2)A(1), 1 (2)B(2), and 1 (2)A(2) states are, respectively, the ground, first excited, and second excited states at the ground-state (1 (2)A(1)) geometry of the ion and at the geometry of the ground-state SO(2) molecule. Based on the CASPT2/ANO-L results for the geometries, we realize that the experimental geometries (determined by assuming the bond lengths to be the same as the neutral ground state of SO(2)) were not accurate. The CASPT2/ANO-S calculations for the potential energy curves as functions of the OSO angle confirm that the 1 (2)B(2) and 1 (2)A(2) states are the results of the Renner-Teller effect in the degenerate (2)Pi(g) state at the linear geometry, and it is clearly shown that the 1 (2)B(2) curve, as the lower component of the Renner splitting, lies below the 1 (2)A(2) curve. The UB3LYP/cc-pVTZ adiabatic excitation energy calculations support the assignments (A to (2)B(2) and B to (2)A(2)) based on the CASPT2/ANO-L calculations.     

High-resolution laser excitation spectroscopy of the A2E-X2A1 transition of SrCH3

High-resolution laser excitation spectroscopy has been used to record the A (2)E-X (2)A(1) electronic transition of SrCH(3) in a laser ablation/molecular jet source. Transitions arising from the K(')=1<--K(")=0, K(')=0<--K(")=1, and K(')=2<--K(")=1 subbands have been observed and assigned. The data were modeled with (2)E and (2)A(1) symmetric top Hamiltonian matrices in a Hund's case (a) basis, using a least squares fitting program. Rotational and fine structure parameters for the A (2)E state were determined. A comparison of the spin-orbit energy separation in the A (2)E state to other strontium containing free radicals showed that the Jahn-Teller effect is negligible. The spin-rotation constants for the A (2)E state were calculated using the pure precession model and were found to be in good agreement with the experimentally determined parameters. These calculations suggest that the A (2)E state of SrCH(3) is not entirely of p orbital character. The rotational constants were used to estimate the structural parameters of SrCH(3) in the A (2)E state. The strontium-carbon bond length was found to decrease by approximately 0.006 A, and the hydrogen-carbon-hydrogen bond angle opened by approximately 0.8 degrees compared to the X (2)A(1) state, similar to the geometry changes observed for CaCH(3).     

Multiconfigurational self-consistent field and multireference internally contracted configuration interaction studies on the excited states of weakly bonded NO2 dimer (N2O4)

In this paper, the vertical excitation energies of total of 32 states of N(2)O(4) including the lowest two singlet states and two triplet states of each of the A(g), B(3u), B(2u), B(1g), B(1u), B(2g), B(3g), and A(u) symmetries were calculated at multiconfigurational self-consistent field (MCSCF) and the multireference internally contracted configuration interaction (MRCI) levels of theory on the active space (15o,16e) with aug-cc-pVDZ basis set. The potential energy curves of the eight singlet states(1 (1)A(g), 1 (1)B(3u), 1 (1)B(2u), 1 (1)B(1g), 1 (1)B(1u), 1 (1)B(2g), 1 (1)B(3g), and 1 (1)A(u)) and eight triplet states (1 (3)A(g), 1 (3)B(3u), 1 (3)B(2u), 1 (3)B(1g), 1 (3)B(1u), 1 (3)B(2g), 1 (3)B(3g), and 1 (3)A(u)) were calculated at MCSCF and MRCI levels of theory on the active space (15o,16e) with aug-cc-pVDZ basis set along the N-N distance. The vertical excitation energies of 1 (1)B(3u), 1 (1)B(2u), and 1 (1)B(1u) states with nonzero transition moment are 4.60 eV (269.6 nm), 6.06 eV (204.6 nm), and 7.71 eV (160.8 nm), respectively, at MRCI level of theory. The photodissociation asymptotics were assigned as NO(2)(X (2)A(1))+NO(2)(X (2)A(1)) for ground state 1 (1)A(g) and the 1 (3)B(1u) state, NO(2)(X (2)A(1))+NO(2)(1 (2)A(2)) for the 1 (1)B(1g), 1 (3)B(1g), 1 (1)A(u), and 1 (3)A(u) states, NO(2)(X (2)A(1))+NO(2)(1 (2)B(1)) for the 1 (1)B(3u), 1 (3)B(3u), 1 (1)B(2g), and 1 (3)B(2g) states, and NO(2)(X (2)A(1))+NO(2)(1 (2)B(2)) for the 1 (1)B(2u), 1 (3)B(2u), 1 (1)B(3g), and 1 (3)B(3g) states.     

活性氮与SO2和SOCl2的传能反应

在流动余辉装置上, 研究了活性氮与SO2和SOCl2之间的反应过程. 在280～500 nm, 观察到了SO2( A1A2,B1B1→X1A1 )和SO2(a3B1→X1A1)的发射光谱. 对比由Ar(3P0,2)与N2碰撞反应产生的纯N2(A3Σu+)与SO2、SOCl2之间反应的实验结果, 可以说明, N2(A3Σu+)在活性氮与SO2的反应中是主要的能量载体, 它与SO2的直接能量转移反应形成了激发态的SO2(A1A2, B1B1); 在活性氮与SOCl2的反应中观测到的激发态SO2(a3B1), 则可能主要是通过N(4S)与SOCl2反应生成的N2O(X1Σ+)和N2(A3Σu+)与SOCl2反应生成的SO(X3Σ－)之间的化学反应过程产生.     

Multi-mycotoxin analysis in eggs using a QuEChERS-based extraction procedure and ultra-high-pressure liquid chromatography coupled to triple quadrupole mass spectrometry

A reliable and rapid method has been developed for the determination of 10 mycotoxins (beauvericin, enniatin A, A1, B1, citrinin, aflatoxin B1, B2, G1, G2 and ochratoxin A) in eggs at trace levels. Ultra-high-pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) has been used for the analysis of these compounds in less than 7 min. Mycotoxins have been extracted from egg samples using a QuEChERS-based extraction procedure (Quick, Easy, Cheap, Effective, Rugged and Safe) without applying any further clean-up step. Extraction, chromatographic and detection conditions were optimised in order to increase sample throughput and sensitivity. Matrix-matched calibration was used for quantification. Blank samples were fortified at 10, 25, 50 and 100 μg kg(-1), and recoveries ranged from 70% to 110%, except for ochratoxin A and aflatoxin G1 at 10 μg kg(-1), and aflatoxin G2 at 50 μg kg(-1). Relative standard deviations were lower than 25% in all the cases. Limits of detection ranged from 0.5 μg kg(-1) (for aflatoxins B1, B2 and G1) to 5 μg kg(-1) (for enniatin A, citrinin and ochratoxin A) and limits of quantification ranged from 1 μg kg(-1) (for aflatoxins B1, B2 and G1) to 10 μg kg(-1) (for enniatin A, citrinin and ochratoxin A). Seven samples were analyzed and aflatoxins B1, B2, G1, G2, and beauvericin were detected at trace levels.     

Cytotoxic hydroxyanthracenones from fruits of Karwinskia parvifolia

Peroxisomicines A1 (1) and A2 (2) are cytotoxic hydroxyanthracenones isolated from the fruits of Karwinskia parvifolia. Peroxisomicine A1 exhibits selective cytotoxicity against several tumor cell lines. In the present investigation three minor constituents were obtained from the same fruit extracts: peroxisomicine A3 (3) and isoperoxisomicines A1 (4) and A2 (5). Compounds 3 and 5 are novel and their structures were determined by spectroscopic methods and molecular modeling. Compounds 1-5 were significantly cytotoxic against hepatoma cell lines.     

Novel dolabellane-type diterpene alkaloids with lipid metabolism promoting activities from the seeds of Nigella sativa

[structure: see text] Four new dolabellane-type diterpene alkaloids, nigellamines A(1) (1), A(2) (2), B(1) (3), and B(2) (4), were isolated from the seeds of Nigella sativa. Their absolute stereostructures were determined on the basis of chemical and physicochemical evidence. Nigellamines A(1) (1), B(1) (3), and B(2) (4) were found to show potent lipid metabolism promoting activity in primary cultured mouse hepatocytes, and their activities were equivalent to that of a PPAR-alpha agonist, clofibrate.     

A novel group of alkaline earth metal amides: syntheses and characterization of M[N(2,6-(i)Pr(2)C(6)H(3))(SiMe(3))](2)(THF)(2) (M = Mg,Ca, Sr,Ba) and the linear,two-coordinate Mg[N(2,6-(i)Pr(2)C(6)H(3))(SiMe(3))](2)

Novel alkaline earth metal aryl-substituted silylamides were prepared using alkane (Mg) and salt elimination reactions (Mg, Ca, Sr, and Ba). The salt elimination regime involved the treatment of the alkaline earth metal iodides with 2 equiv of the respective potassium amide KNDiip(SiMe(3)), (Diip = 2,6-i-Pr(2)C(6)H(3)). The organomagnesium source for the alkane elimination was ((n)()Bu/(s)()Bu)(2)Mg. All compounds were characterized using (1)H, (13)C NMR, and IR spectroscopy, in addition to X-ray crystallography (except Mg[NDiip(SiMe(3))](2)THF(2)). Crystal data with Mo Kalpha (lambda = 0.710 73 A) are as follows: Mg[NDiip(SiMe(3))](2), 1, a = 9.4687(6) A, b = 9.6818(6) A, c = 17.9296(1) A, alpha = 96.487(1) degrees, beta = 94.537(1) degrees, gamma = 89.222(1) degrees, V = 1608.8(2) A(3), Z = 2 (two independent molecules), triclinic, space group P(-)1, R1 (all data) = 0.0508; (n)()BuMg[NDiip(SiMe(3))]THF(2), 2, a = 9.5413(1) A, b = 16.493(2) A, c = 9.8218(1) A, beta = 108.149(2) degrees, V = 1468.7(4) A(3), Z = 2, monoclinic, space group P2(1), R1(all data) = 0.1232; Ca[NDiip(SiMe(3))](2)THF(2), 4, a = 9.7074(1) A, b = 20.9466(4) A, c = 21.6242(3) A, alpha = 73.573(1) degrees, beta = 78.632(1) degrees, gamma = 89.621(1) degrees, V = 4129.1(1) A(3), Z = 4 (two independent molecules), triclinic, space group P(-)1, R1 (all data) = 0.0902; Sr[NDiip(SiMe(3))](2)THF(2), 5, a = 20.5874(5) A, b = 9.8785(2) A, c = 20.8522(5) A, beta = 102.035(2) degrees, V = 4147.6(2) A(3), Z = 4 (two independent molecules), monoclinic, space group P2/n, R1 (all data) = 0.0756; Ba[NDiip(SiMe(3))](2)THF(2), 6, a = 20.5476(2) A, b = 10.0353(2) A, c = 20.9020(4) A, beta = 101.657(1) degrees, V = 4221.0(1) A(3), Z = 4 (two independent molecules), monoclinic, space group P2/n, R1 (all data) = 0.0573.     

Ab initio calculations on SF2 and its low-lying cationic states: anharmonic Franck-Condon simulation of the UV photoelectron spectrum of SF2

Geometry optimization calculations were carried out on the (approximate)X(1)A(1) state of SF2 and the (approximate)X(2)B(1), (approximate)A(2)A(1), (approximate)B(2)B(2), (approximate)C(2)B(2), (approximate)D(2)A(1), and (approximate)E(2)A(2) states of SF2(+) employing the restricted-spin coupled-cluster single-double plus perturbative triple excitation [RCCSD(T)] method and basis sets of up to the augmented correlation-consistent polarized quintuple-zeta [aug-cc-pV(5+d)Z] quality. Effects of core electron (S 2s(2)2p(6) and F 1s(2) electrons) correlation and basis set extension to the complete basis set limit on the computed minimum-energy geometries and relative electronic energies (adiabatic and vertical ionization energies) were investigated. RCCSD(T) potential energy functions (PEFs) were calculated for the (approximate)X(1)A(1) state of SF2 and the low-lying states of SF2(+) listed above employing the aug-cc-pV(5+d)Z and aug-cc-pV5Z basis sets for S and F, respectively. Anharmonic vibrational wave functions of these neutral and cationic states of SF2, and Franck-Condon (FC) factors of the lowest four one-electron allowed neutral photoionizations were computed employing the RCCSD(T) PEFs. Calculated FC factors with allowance for Duschinsky rotation and anharmonicity were used to simulate the first four photoelectron bands of SF2. The agreement between the simulated and observed first bands in the He I photoelectron spectrum reported by de Leeuw et al. [Chem. Phys. 34, 287 (1978)] is excellent. Our calculations largely support assignments made by de Leeuw et al. on the higher ionization energy bands of SF2.     

Synthesis and structure of isomeric palladium(II)-pyrazole chelate complexes with and without an N-H group as hydrogen bond donor

Four new ligands containing a pyrazole ring and either a phosphine or thioether were prepared and converted to their cis-dichloropalladium(II) complexes. Two of the ligands are especially notable for the attachment of a side chain at pyrazole carbon, rather than at nitrogen. The new metal complexes include dichloro[3-(diphenylphosphinomethyl)pyrazole]palladium(II) (1-PdCl2) and dichloro[3-(methylthiomethyl)pyrazole]palladium(II) (2-PdCl2), which both feature an N-H group as a potential proton or hydrogen bond donor. For comparison, isomeric complexes lacking an NH group were prepared: dichloro[1-(diphenylphosphinomethyl)pyrazole]palladium(II) (3-PdCl2) and dichloro[1-(methylthiomethyl)pyrazole]palladium(II) (4-PdCl2). As determined by X-ray crystallography, all four complexes were found to have slightly distorted square planar geometry. Complexes 1-PdCl2 and 2-PdCl2, which contain an NH group, exhibit both intermolecular and intramolecular hydrogen bonding, whereas isomers 3-PdCl2 and 4-PdCl2 do not. Single-crystal X-ray structure determinations on the following compounds are reported: 1-PdCl2, space group P1, a = 8.4488(9) A, b = 8.9175(13) A, c = 12.731(2) A, Z = 2, V = 871.8(2) A3; 2-PdCl2, space group Pbca, a = 10.8827(10) A, b = 11.7721(7) A, c = 14.874(2) A, Z = 8, V = 1905.6 A3; 3-PdCl2, space group P2(1)/c, a = 20.520(2) A, b = 12.549(2) A, c = 13.9784(13) A, Z = 8, V = 3401.1(6) A3; 4-PdCl2, space group Pbca, a = 10.6545(10) A, b = 12.0205(11) A, c = 14.6474(14) A, Z = 8, V = 1875.9(3) A3.     

Haptoglobin subtyping with anti-haptoglobin alpha chain antibodies

Specific antibodies against the human haptoglobin (HP) alpha chain were raised and used for immunoblotting after isoelectric focusing to determine Hp alpha subtypes in a reproducible and simplified manner. By eliminating the staining of the HP beta chain, HP alpha subtypes were visualized more precisely and simply than by previously reported methods. Subtypes of a total of 1211 sera, obtained from two different populations in Japan, were examined by the new method. Four HP alpha subtypes (HP 1S-1S,2FS-1S, 2FS-2FS and 2FS-2SS) and five subtypes combined with a new variant (HP 2FS-1V1, 2V1-1S, 2FS-2V1, 2FS-2V2 and 2FS-2V3) were observed. HP 1V1 belonged to HP alpha 1, and HP 2V1, 2V2 and 2V3 belonged to HP alpha 2, and their alleles were designated HP A*1V1, HP A*2V1, HP A*2V2 and HP A*2V3, respectively. The allele frequencies were calculated to be as follows: HP A*1S, 0.2597; HP A*1V1, 0.0004; HP A*2FS, 0.7333; HP A*2SS, 0.0008; HP A*2V1, 0.0045; HP A*2V2, 0.0008; and HP A*2V3, 0.0004. The allele frequency of HP A*2SS, which is common in the European population, is less frequent than HP A*2V1 in the Japanese population.