Tracking an electronic wave packet in the vicinity of a conical intersection.

This work treats the impact of vibrational coherence on the quantum efficiency of a dissipative electronic wave packet in the vicinity of a conical intersection by monitoring the time-dependent wave packet projection onto the tuning and the coupling mode. The vibrational coherence of the wave packet is tuned by varying the strength of the dissipative vibrational coupling of the tuning and the coupling modes to their thermal baths. We observe that the most coherent wave packet yields a quantum efficiency of 93%, but with a large transfer time constant. The quantum yield is dramatically decreased to 50% for a strongly damped incoherent wave packet, but the associated transfer time of the strongly localized wave packet is short. In addition, we find for the strongly damped wave packet that the transfer occurs via tunneling of the wave packet between the potential energy surfaces before the seam of the conical intersection is reached and a direct passage takes over. Our results provide direct evidence that vibrational coherence of the electronic wave packet is a decisive factor which determines the dynamical behavior of a wave packet in the vicinity of the conical intersection.

Examining the Critical Roles of Protons in Facilitating Oxidation of Chloride Ions by Permanganates: A Cluster Model Study.

The oxidation power of permanganates (MnO4(-)) is known to be strongly dependent on pH values, and is greatly enhanced in acidic solutions, in which, for example, MnO4(-) can even oxidize Cl(-) ions to produce Cl2 molecules. Although such dependence has been ascribed due to the different reduced states of Mn affordable in different pH media, a molecular level understanding and characterization of initial redox pair complexes available in different pH solutions is very limited. Herein, we report a comparative study of [MnO4](-) and [MnO4·Sol](-) (Sol = H2O, KCl, and HCl) anion clusters by negative ion photoelectron spectroscopy (NIPES) and theoretical computations to probe chemical bonding and electronic structures of [MnO4·Sol](-) clusters, aimed to obtain a microscopic understanding of how MnO4(-) interacts with surrounding molecules. Our study shows that H2O behaves as a solvent molecule, KCl is a spectator bound by pure electrostatic interactions, both of which do not influence the MnO4(-) identity in their respective clusters. In contrast, in [MnO4·HCl](-), the proton is found to interact with both MnO4(-) and Cl(-) with appreciable covalent characters, and the frontier MOs of the cluster are comprised of contributions from both MnO4(-) and Cl(-) moieties. Therefore, the proton serves as a chemical bridge, bringing two negatively charged redox species together to form an intimate redox pair. By adding more H(+) to MnO4(-), the oxygen atom can be taken away in the form of a water molecule, leaving MnO4(-) as an electron deficient MnO3(+) species, which can subsequently oxidize Cl(-) ions.

Solvent effect-driven assembly of W/Cu/S cluster-based coordination polymers from the cluster precursor [Et4N][Tp*WS3(CuBr)3] and CuCN: isolation, structures and enhanced NLO responses.

We herein describe a coordination polymer system built upon the reactions of a W/Cu/S cluster precursor [Et4N][Tp*WS3(CuBr)3] (1, Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with three equivalents of CuCN through solvent modulation. Four coordination polymers, namely, [Tp*WS3Cu3(µ3-DMF)(CN)3Cu(Py)] (2), [Tp*WS3Cu3(µ3-DMF)(CN)3Cu] (3), [Tp*WS3Cu3(µ3-DMF)(CN)3Cu]·4aniline (4·4aniline) and [Tp*WS3Cu3(µ3-DMF)(CN)3Cu]·2(DMF)0.5 (5·2(DMF)0.5), are isolated in different solvent systems and characterized by means of elemental analysis, FT-IR, UV-Vis, ESI-MS and single-crystal X-ray diffraction. Compounds 2-5 feature µ3-DMF association with the nest-shaped [WS3Cu3] cluster cores, yielding cubane-type [WS3Cu3O] clusters which are further linked to single Cu(I) ions through CN bridges to provide 1D or 2D structures. Compounds 3-5 have identical chemical compositions in their main fragments but with distinctively different structural features, and are therefore topological isomers. Compound 2 has a ladder-type structure in which the side rails contain alternately linked cluster cores and Cu(I) ions. Compound 3 has a 2D (6,3) network with alternately arranged cluster cores and Cu(I) ions. Both 4 and 5 have 2D structures with 4·8(2) topology. In 4, a pair of cluster cores and Cu(I) ions form a 4-membered ring which is further linked to four equivalent rings through four CN ligands via a cluster core-to-Cu arrangement; while in the structure of 5, the same 4-membered rings as those in 4 are extended to equivalent rings via a cluster core-to-cluster and Cu-to-Cu arrangement. The hyperpolarizabilities (γ) of the polymeric networks exhibit an enhancement of more than 10 times compared to their parent cluster, 1.

Photoelectron spectroscopy and theoretical studies of anion-π interactions: binding strength and anion specificity.

Proposed in theory and then their existence confirmed, anion-π interactions have been recognized as new and important non-covalent binding forces. Despite extensive theoretical studies, numerous crystal structural identifications, and a plethora of solution phase investigations, anion-π interaction strengths that are free from complications of condensed-phase environments have not been directly measured in the gas phase. Herein we present a joint photoelectron spectroscopic and theoretical study on this subject, in which tetraoxacalix[2]arene[2]triazine 1, an electron-deficient and cavity self-tunable macrocyclic, was used as a charge-neutral molecular host to probe its interactions with a series of anions with distinctly different shapes and charge states (spherical halides Cl(-), Br(-), I(-), linear thiocyanate SCN(-), trigonal planar nitrate NO3(-), pyramidic iodate IO3(-), and tetrahedral sulfate SO4(2-)). The binding energies of the resultant gaseous 1 : 1 complexes (1·Cl(-), 1·Br(-), 1·I(-), 1·SCN(-), 1·NO3(-), 1·IO3(-) and 1·SO4(2-)) were directly measured experimentally, exhibiting substantial non-covalent interactions with pronounced anion-specific effects. The binding strengths of Cl(-), NO3(-), IO3(-) with 1 are found to be strongest among all singly charged anions, amounting to ca. 30 kcal mol(-1), but only about 40% of that between 1 and SO4(2-). Quantum chemical calculations reveal that all the anions reside in the center of the cavity of 1 with an anion-π binding motif in the complexes' optimized structures, where 1 is seen to be able to self-regulate its cavity structure to accommodate anions of different geometries and three-dimensional shapes. Electron density surface and charge distribution analyses further support anion-π binding formation. The calculated binding energies of the anions and 1 nicely reproduce the experimentally estimated electron binding energy increase. This work illustrates that size-selective photoelectron spectroscopy combined with theoretical calculations represents a powerful technique to probe anion-π interactions and has potential to provide quantitative guest-host molecular binding strengths and unravel fundamental insights in specific anion recognitions.

Temporal lobe epilepsy with amygdala enlargement: a subtype of temporal lobe epilepsy.

BACKGROUND: Some recent studies suggest that some imaging-negative temporal lobe epilepsy (TLE) had significant amygdala enlargement (AE). Contradictory data were also reported in previous studies regarding the association between AE and TLE. The present study was to investigate the clinical characters of a group of TLE with AE and compare the amygdala volume of the same patient before and after antiepileptic drugs treatment by a larger sample size. METHODS: This study recruited 33 mesial TLE patients with AE and 35 healthy volunteers. The clinical history, seizure semiology, electroencephalogram (EEG), fluorodeoxyglucose-positron emission tomography (FDG-PET) and amygdala volume were investigated. The amygdala volume were compared between ipsilateral and contralateral sides, TLE patients and 35 healthy controls, and patients at first and follow-up visit by 3.0 T MRI. RESULTS: Average seizure onset age was 42.0 years (SD 14.3). All patients had complex partial seizures, fourteen had occasional generalized tonic-clonic seizures which often happened during sleep. Ninety percent patients suffered from anxiety or depression. Thirty percent patients had memory decline. Interictal epileptiform discharges appeared predominantly in the anterior or inferior temporal area ipsilateral to AE. Interictal FDG-PET showed regional glucose hypometabolism in the ipsilateral temporal lobe. No hippocampal sclerosis (HS) was suspected in all patients. 22 patients demonstrated good seizure control and significantly reduced volume of the enlarged amygdala after treatment (P < 0.01). The other 11 patients showed initial response to treatment, followed by a gradual increase in seizure frequency over time, and no volume change of the enlarged amygdala after treatment. CONCLUSIONS: TLE with AE probably represents a distinct nosological and probably less homogeneous syndrome which is most likely a subtype of TLE without ipsilateral HS. The chronic and long lasting inflammatory processes or focal cortical dysplasia could lead to amygdala enlargement possibly.

Six [Tp*WS3Cu2]-based clusters derived from [Et4N][Tp*WS3], Cu(I) salts and phosphine ligands: syntheses, structures and enhanced third-order NLO properties.

Treatment of [Et4N][Tp*WS3] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with CuX (X = Br, SCN) and PPh3 or 1,1-bis(diphenylphosphino)methane (dppm) produced two neutral trinuclear clusters [Tp*W(µ3-S)(µ-S)2Cu2Br(PPh3)] (2) and [Tp*W(µ3-S)(µ-S)2Cu2(SCN)(dppm)]2·MeCN·Et2O (3·MeCN·Et2O). Reactions of 1 with [Cu(MeCN)4]PF6, NH4PF6 and 1,3-bis(diphenylphosphino)propane (dppp), N,N-bi(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy), N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylenediamine (dppeda), or 1,4-N,N,N',N'-tetra(diphenylphosphanylmethyl)benzenediamine (dpppda) afforded four clusters containing butterfly-shaped [Tp*WS3Cu2] cores, [Tp*W(µ3-S)(µ-S)2Cu2(dpppds)](PF6)·1.25MeCN (dpppds = 1,3-bis(diphenylphosphino)propane disulfide) (4·1.25MeCN), [Tp*W(µ3-S)(µ-S)2Cu2(bdppmapy)](PF6)·3MeCN (5·3MeCN) and {[Tp*W(µ3-S)(µ-S)2Cu2]2(L)]}(PF6)2·Sol (6·Et2O: L = dppeda, Sol = Et2O; 7·1.25MeCN: L = dpppda, Sol = 1.25MeCN). Compounds 2-7 were characterized by elemental analysis, IR, UV-Vis, (1)H and (31)P{(1)H} NMR spectra, electrospray ion mass spectra (ESI-MS) and single-crystal X-ray diffraction. Compound 2 or 3 has a butterfly-shaped [Tp*WS3Cu2] core in which one [Tp*WS3] unit binds two Cu(I) centers via one µ3-S and two µ-S atoms. In the cationic structure of 4 or 5, one in situ-formed dpppds or bdppmapy combines with the [Tp*WS3Cu2] core via each of its two S atoms or two P atoms coordinated at each Cu(I) center. In the bicationic structure of 6 or 7, two [Tp*WS3Cu2] cores are linked by one dppeda or dpppda bridge to form a bicyclic structure. The isolation of 2-7 with unstable [Tp*WS3Cu2] cores may be ascribed to the coordination of P- or S-donor ligands at Cu(i) centers of these cores. The third-order nonlinear optical (NLO) properties of 2-7 in DMF were also investigated by using the femtosecond degenerate four-wave mixing (DFWM) technique at 800 nm.

Vibrationally Resolved Photoelectron Spectroscopy of the Model GFP Chromophore Anion Revealing the Photoexcited S1 State Being Both Vertically and Adiabatically Bound against the Photodetached D0 Continuum.

The first excited state of the model green fluorescence protein (GFP) chromophore anion (S1) and its energy level against the electron-detached neutral radical D0 state are crucial in determining the photophysics and the photoinduced dynamics of GFP. Extensive experimental and theoretical studies, particularly several very recent gas-phase investigations, concluded that S1 is a bound state in the Franck-Condon vertical region with respect to D0. However, what remains unknown and challenging is if S1 is bound adiabatically, primarily due to lack of accurate experimental measurements as well as due to the close proximity in energy for these two states that even sophisticated high-level ab initio calculations cannot reliably predict. Here, we report a negative ion photoelectron spectroscopy study on the model GFP chromophore anion, the deprotonated p-hydroxybenzylidene-2,3-dimethylimidazolinone anion (HBDI(-)) taken under low-temperature conditions with improved energy resolution. Despite the considerable size and low symmetry of the molecule, resolved vibrational structures were obtained with the 0-0 transition being the most intense peak. The adiabatic (ADE) and vertical detachment (VDE) energies therefore are determined both to be 2.73 ± 0.01 eV, indicating that the detached D0 state is 0.16 eV higher in energy than the photon excited S1 state. The accurate ADE and VDE values and the well-resolved photoelectron spectra reported here provide much needed robust benchmarks for future theoretical investigations.

Covalently bound tetracoordinated organoborons as superhalogens: a combined negative ion photoelectron spectroscopy and theoretical study.

Molecular species with electron affinities (EAs) larger than that of the chlorine atom (3.6131 eV) are superhalogens. The corresponding negative ions, namely, superhalogen anions, are intrinsically very stable with high electron binding energies (EBEs) and widely exist as building blocks of bulk materials and ionic liquids. The most common superhalogen anions proposed and experimentally confirmed to date are either ionic salts or compact inorganic species. Herein, we report a new class of superhalogen species, a series of tetracoordinated organoboron anions [BL4](-) (L = phenyl (1), 4-fluorophenyl (2), 1-imidazolyl (3), L4 = H(pyrazolyl)3 (4)) with bulky organic ligands covalently bound to the central B atom. Negative ion photoelectron spectroscopy (NIPES) reveals that all of these anions possess EBEs higher than that of Cl(-) with the adiabatic/vertical detachment energy (ADE/VDE) of 4.44/4.8 (1), 4.78/5.2 (2), 5.08/5.4 (3), and 4.59/4.9 eV (4), respectively. First-principles calculations confirmed high EBEs of [BL4](-) and predicted that these anions are thermodynamically stable against fragmentation. The unraveled superhalogen nature of these species provides a molecular basis to explain the wide-ranging applications of tetraphenylborate (TPB) (1) and trispyrazolylborate (Tp) (4) in many areas spanning from industrial waste treatment to soft material synthesis and organometallic chemistry.

Seizure semiology and electroencephalography in young children with lesional temporal lobe epilepsy.

PURPOSE: This study aimed to discuss the clinical features of seizure semiology and electroencephalography (EEG) in young children with lesional temporal lobe epilepsy (TLE). METHOD: Children with lesional TLE received presurgical evaluation for intractable epilepsy. They were followed up for more than one year after temporal lobectomy. We reviewed the medical history and video-EEG monitoring of children with TLE to analyze the semiology of seizures and EEG findings and compared the semiology of seizures and EEG findings of childhood TLE and adult TLE. RESULTS: A total of 84 seizures were analyzed in 11 children (aged 23-108 months). The age of seizure onset was from 1 month to 26 months (a mean of 17.6 months). All of the patients exhibited prominent motor manifestations including epileptic spasm, tonic seizure, and unilateral clonic seizure. Seven children manifested behavioral arrest similar to an automotor seizure in adult TLE but with a shorter duration and higher frequency. The automatisms were typically orofacial, whereas manual automatisms were rarely observed. The EEG recordings revealed that diffuse discharge patterns were more common in younger children, whereas focal or unilateral patterns were more typical in older children. All of the patients were seizure-free after temporal lobectomy with more than one-year follow-up. All of the children had a mental development delay or regression; however, there was improvement after surgery, especially in those with surgery performed early. CONCLUSION: In contrast to TLE in adults, young children with lesional TLE probably represent a distinct nosological and probably less homogeneous syndrome. Although they had generalized clinical and electrographic features, resective epilepsy surgery should be considered as early as possible to obtain seizure control and improvement in mental development.

Patients with risk factors have higher plasma levels of lysophosphatidic acid: a promising surrogate marker for blood platelet activation.

Although basic medical studies have shown that lysophosphatidic acid (LPA) has an important relationship to activated blood platelets, we know little about this from clinical experience. This pilot study examined plasma LPA levels in patients with a risk of thrombotic events and evaluated the effects of aspirin on plasma LPA levels. In this basically cross-sectional study, we recruited 1352 patients with either hypertension or hyperlipidemia and 670 controls without any risk factors. Patients with risk factors had significantly higher plasma LPA levels than controls, the mean of LPA = 3.12 ±â€Š2.24 vs. 2.57 ±â€Š1.96 µmol/l, P < 0.001. The patients who had been taking aspirin had relatively lower plasma LPA levels compared with those who did not take aspirin, χ = 43.8, odds ratio (OR) [95% confidence interval (CI)] = 2.76 (2.03-3.75). For the hypertension group, χ = 23.1, OR (95% CI) = 3.44 (2.03-5.82), P < 0.001; for the hyperlipidemia group, χ = 22.9, OR (95% CI) = 2.53 (1.72-3.74), P < 0.001. Patients with a risk factor had higher plasma LPA levels compared with controls. Administration of aspirin may decrease elevated plasma LPA levels. This pilot clinical observation indicates that plasma LPA is worth to be studied further.

Assembly of new Mo/Cu/S clusters from [Et4N][Tp*MoS(S4)] and Cu(I) salts: syntheses, structures and third-order nonlinear optical properties.

Reactions of [Et4N][Tp*MoS(S)4] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with 3 equiv. of CuX (X = Cl, Br, I, CN) or [Cu(MeCN)4]ClO4 in CH2Cl2-MeCN or CH2Cl2-DMF afforded [Et4N]2[Tp*Mo(µ3-S)3(CuCl)3(µ3-Cl)] (2), [Et4N][Tp*Mo(µ3-S)3(CuX)3] (3: X = Br; 4: X = I), [Et4N][Tp*MoO(µ-S)2(CuX)] (5: X = I; 6: X = CN) and [Tp*Mo(µ3-S)3Cu3(µ3-S')]4 (7). Compounds 2-7 were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, electrospray ion mass spectra (ESI-MS) and X-ray crystallography. The cluster dianion of 2 has a complete cubane-like [Tp*Mo(µ3-S)3(CuCl)3(µ3-Cl)] structure while the anion of 3 or 4 consists of an incomplete cubane-like [Tp*Mo(µ3-S)3(CuX)3] structure. The anion of 5 or 6 has a binuclear structure, in which one [Tp*MoO(µ-S)2] moiety and one CuX unit are linked by a pair of µ-S atoms. The structure of 7 may be considered as a supercube whose eight corners are occupied by four incomplete cubane-like [Tp*Mo(µ3-S)3Cu3] fragments and four µ3-S' atoms. The third-order nonlinear optical (NLO) properties of 2-6 in DMF were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80 fs pulse width at 800 nm. Compounds 2-6 exhibited good NLO performances and their NLO responses were enhanced relative to that of 1.

[PyH][{TpMo(µ(3)-S)4Cu3}4(µ(12)-I)]: a unique tetracubane cluster derived from the S-S bond cleavage and the iodide template effects and its enhanced NLO performances.

Reactions of [Et4N][TpMoS(S4)] with three equiv. of CuI in MeCN or in pyridine gave rise to one dicubane and one tetracubane anionic clusters, [Et4N]2[{TpMo(µ3-S)3Cu3I}2(µ-I){Cu(µ-I)2(µ4-I)2}] and [PyH][{TpMo(µ3-S)4Cu3}4(µ12-I)], and their third-order nonlinear optical (NLO) responses were greatly enhanced relative to that of the precursor.

Theoretical studies on molecular and structures of mono- and binuclear chromium carbazole derivatives for optoelectronics.

Studies on the molecular geometries, electronic properties and second-order nonlinearities of a series of mono- and binuclear chromium carbazole complexes: (N-vinylcarbazole)Cr(CO)(3) (M1), (N-vinylcarbazole)Cr(CO)(2)PPh(3) (M2), (CO)(3)Cr(N-vinylcarbazole)Cr(CO)(3) (B1), and (CO)(3)Cr(N-vinylcarbazole)Cr(CO)(2)PPh(3) (B2) were carried out, using the density functional theory (DFT) at the B3LYP//LanL2DZ/6-31G(d) level. The experimental singlet metal-to-ligand charge transfer ((1)MLCT) spectra of these complexes can also be well simulated and discussed by the time-dependent DFT (TDDFT) at the B3LYP//LanL2DZ/6-311+G(d) level associated with the polarizable continuum model (PCM). The computational results show that an unusual characteristic of chromium carbazole structures is explained in terms of interaction between frontier molecular orbitals of the metal and its ligands. The highest occupied molecular orbitals (HOMOs) of these complexes are composed of a set of distorted degenerated Cr 3d orbitals, whereas the lowest unoccupied molecular orbitals (LUMOs) are predominantly the N-vinylcarbazole ligand π* orbitals. The HOMO-LUMO energy gaps decrease in the order NVC > M1 > B1 > M2 > B2. The considerable coupling between the carbazole and (CO)(3) in M1 creates an asymmetric environment about the chromium atom, leading to modest second-order responses. The PPh(3) ligand is acting as a donor which increases the donating strength of the d(π) orbitals in chromium carbazole species, resulting in the large electronic asymmetry in M2. As for the binuclear chromium carbazole chromophores, a wide-range (1)MLCT band and large oscillator strength are found, allowing for the electronic interactions between two metal centers which can be modified by altering the ligand bound to the metals to induce peculiar asymmetry. Essentially, Cr(CO)(3) acceptor and Cr(CO)(2)PPh(3) donor units in B2 make significant contribution to the charge-transfer process or NLO responses via conventional push-pull chromophoric architecture.

[Application of intracranial electrode for locating epileptogenic zone for temporal lobe epilepsy surgery].

OBJECTIVE: To explore the application of intracranial electrodes (IE) for temporal lobe epilepsy (TLE) surgery and assess the clinical utility of intracranial video electroencephalography (IVEEG). METHODS: The clinical data of 60 TLE patients undergoing implantation of IE were reviewed retrospectively. Cortical subdural strip, grids and depth electrodes were implanted by sphenotresia, bone disc craniotomy or stereotactic technology. RESULTS: The implanted electrodes were as follows: frontal-temporal lobe cortical strip (n = 34), frontal-anterior temporal-occipitotemporal lobe cortical strip (n = 7), bilateral temporal lobe cortical strip (n = 7), combined temporal lobe strip & depth (n = 7), anterior temporal-occipitotemporal junction cortical strip (n = 3) and combined strip & grid (n = 2). The following procedures were performed: anterior temporal lobectomy (ATL) (n = 50), combined ATL & frontal focal cortical resection (n = 7), combined ATL & callosotomy (n = 1) and combined neocortex epileptogenic focus resection & amygdalohippocampectomy (n = 2). CONCLUSION: IVEEG is effective and important for the localization of epileptogenic focus in patients with intractable temporal lobe epilepsy.

Four [Tp*W(µ3-S)3Cu3(µ3-Br)]-based clusters: synthesis, structural characterization and third-order NLO properties.

Treatment of [Et(4)N][Tp*W(µ(3)-S)(3)(CuBr)(3)] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with an excess of α-methylpyridine (α-MePy) and NH(4)PF(6) in CH(2)Cl(2) afforded a cationic cluster [Tp*W(µ(3)-S)(3)Cu(3)(α-MePy)(3)(µ(3)-Br)](PF(6)) (2) while the reaction of 1 with an excess of 1,4-pyrazine (1,4-pyz) and NH(4)PF(6) in MeCN-CH(2)Cl(2) at 65 °C produced a polymeric cluster [Tp*W(µ(3)-S)(3)Cu(3)(1,4-pyz)((1,4-pyz)(0.5))(2)(µ(3)-Br)][Tp*W(µ(3)-S)(3)(CuBr)(3)] (3). Reactions of 1 with melamine (MA) in 1:1 or 1:2 gave rise to another polymeric cluster [{Tp*W(µ(3)-S)(3)Cu(3)Br(µ(3)-Br)}(2)(MA)(2)] (4) and a neutral cluster [Tp*W(µ(3)-S)(3)Cu(3)Br(µ(3)-Br)(MA)(2)] (5), respectively. Compounds 2-5 were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, electrospray ionization (ESI) mass spectra and X-ray crystallography. The cation of 2 has a cubane-like [Tp*W(µ(3)-S)(3)Cu(3)(µ(3)-Br)] structure with each α-MePy ligand coordinated at one Cu(i) center. For 3, each [Tp*W(µ(3)-S)(3)Cu(3)(µ(3)-Br)] core is interconnected by 1,4-pyz bridges to form a 1D cationic zigzag chain with the [Tp*W(µ(3)-S)(3)(CuBr)(3)](-) anions arranged along its two sides. For 4, each [Tp*W(µ(3)-S)(3)Cu(3)(µ(3)-Br)] core is interlinked by MA bridges to afford a 1D spiral chain. 5 adopts a cubane-like [Tp*W(µ(3)-S)(3)Cu(3)(µ(3)-Br)] structure in which one terminal Br and two MA ligands are coordinated at three Cu centers. The third-order nonlinear optical (NLO) properties of 1-5 in DMF were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80 fs pulse width at 800 nm. Compounds 1-5 exhibit good NLO responses, and 3 and 4 possess the largest second-order hyperpolarizability γ values among the known W/Cu/S clusters bearing the [Tp*WS(3)] unit.

Assembly of bicyclic or monocyclic clusters from [(η5-C5Me5)2Mo2(µ3-S)4(CuMeCN)2]2+ with tetraphosphine or N,P mixed ligands: syntheses, structures and enhanced third-order NLO performances.

Reactions of the preformed cluster [(η(5)-C(5)Me(5))(2)Mo(2)(µ(3)-S)(4)Cu(2)(MeCN)(2)](ClO(4))(2) (1) with two tetraphosphine ligands, 1,4-N,N,N',N'-tetra(diphenylphosphanylmethyl)benzene diamine (dpppda) and N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylene diamine (dppeda), produced two bicyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(µ(3)-S)(4)Cu(2)](2)(L)}(ClO(4))(4) (3: L = dpppda; 4: L = dppeda). Analogous reactions of 1 or [(η(5)-C(5)Me(5))(2)Mo(2)(µ(3)-S)(4)Cu(2)(MeCN)(2)](PF(6))(2) (2) with two N,P mixed ligands, N,N-bi(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) and N-diphenylphosphanylmethyl-4-aminopyridine (dppmapy), afforded two monocyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(µ(3)-S)(4)Cu(2)](2)(L)(2)}X(4) (5: L = bdppmapy, X = ClO(4); 6: L = dppmapy, X = PF(6)). Compounds 3-6 were fully characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H and (31)P{(1)H} NMR spectra, ESI-MS and single-crystal X-ray crystallography. In the tetracations of 3-6, two cubane-like [Mo(2)(µ(3)-S)(4)Cu(2)] cores are linked either by one dpppda or dppeda bridge to form a bicyclic structure or by a pair of bdppmapy or dppmapy bridges to afford a monocyclic structure. The third-order nonlinear optical (NLO) properties of 1 and 3-6 in MeCN were also investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 50 fs pulse width at 800 nm. Compounds 3-6 exhibited enhanced third-order NLO performances relative to that of 1.

Construction of halide-bridged tungsten-copper-sulfide double cubanelike clusters from a new precursor [(Tp*WS2)2(µ-S2)].

Treatment of [Et(4)N][Tp*WS(3)] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS(2))(2)(µ-S(2))] (2). Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH(2)Cl(2) or CHCl(3) formed three neutral W/Cu/S clusters [{Tp*W(µ(3)-S)(3)Cu(3)(µ-Cl)}(2)Cu(µ-Cl)(2)(µ(7)-Cl)(MeCN)](2) (3), [{Tp*W(µ(3)-S)(3)Cu(3)}(2)Br(µ-Br)(2)(µ(4)-Br)(MeCN)] (4), and [{Tp*W(µ(3)-S)(3)Cu(3)}(2){Cu(2)(µ-I)(4)(µ(3)-I)(2)}] (5), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et(4)NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et(4)N][{Tp*W(µ(3)-S)(3)Cu(3)X}(2)(µ-X)(2)(µ(4)-X)] (6: X = Cl; 7 X = Br). Compounds 2-7 were characterized by elemental analysis, IR, UV-vis, (1)H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray crystallography. The dimeric structure of 2 can be viewed as two [Tp*WS(2)] fragments in which two W atoms are connected by one S(2)(2-) dianion. Compounds 3-7 all possess unique halide-bridged double cubanelike frameworks. For 3, two [Tp*W(µ(3)-S)(3)Cu(3)](2+) dications are linked via a µ(7)-Cl(-) bridge, two µ-Cl(-) bridges, and a [Cu(MeCN)(µ-Cl)(2)](+) bridge. For 4, one [Tp*W(µ(3)-S)(3)Cu(3)(MeCN)](2+) dication and one [Tp*W(µ(3)-S)(3)Cu(3)Br](+) cation are linked via a µ(4)-Br(-) and two µ-Br(-) bridges. For 5, the two [Tp*W(µ(3)-S)(3)Cu(3)](2+) dications are bridged by a linear [(µ-I)(2)Cu(µ(3)-I)(2)Cu(µ-I)(2)](4+) species. For 6 and 7, two [Tp*W(µ(3)-S)(3)Cu(3)X](+) cations are linked by a µ(4)-X(-) and two µ-X(-) bridges (X = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2-7 in MeCN/CH(2)Cl(2) were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique.

[Raman spectra of monkey cerebral cortex tissue].

Monkey cerebral cortex, an important part in the brain to control action and thought activities, is mainly composed of grey matter and nerve cell. In the present paper, the in situ Raman spectra of the cerebral cortex of the birth, teenage and aged monkeys were achieved for the first time. The results show that the Raman spectra for the different age monkey cerebral cortex exhibit most obvious changes in the regions of 1000-1400 and 2800-3000 cm(-1). With monkey growing up, the relative intensities of the Raman bands at 1313 and 2885 cm(-1) mainly assigned to CH2 chain vibrational mode of lipid become stronger and stronger whereas the relative intensities of the Raman bands at 1338 and 2932 cm(-1) mainly assigned to CH3 chain vibrational mode of protein become weaker and weaker. In addition, the two new Raman bands at 1296 and 2850 cm(-1) are only observed in the aged monkey cerebral cortex, therefore, the two bands can be considered as a character or "marker" to differentiate the caducity degree with monkey growth In order to further explore the changes, the relative intensity ratios of the Raman band at 1313 cm(-1) to that at 1338 cm(-1) and the Raman band at 2885 cm(-1) to that at 2 932 cm(-1), I1313/I1338 and I2885/I2932, which are the lipid-to-protein ratios, are introduced to denote the degree of the lipid content. The results show that the relative intensity ratios increase significantly with monkey growth, namely, the lipid content in the cerebral cortex increases greatly with monkey growth. So, the authors can deduce that the overmuch lipid is an important cause to induce the caducity. Therefore, the results will be a powerful assistance and valuable parameter to study the order of life growth and diagnose diseases.

Stepwise addition of CuNCS onto [Et(4)N][Tp*WS(3)]: design, syntheses, structures and third-order nonlinear optical properties.

Stepwise reactions of [Et(4)N][Tp*WS(3)] () (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 1-4 equiv. of CuNCS (and Et(4)NBr in the case of three equiv. of CuNCS) afforded the [1 + 1] to [1 + 4] addition products [Et(4)N][Tp*WS(mu-S)(2)(CuNCS)].0.5CH(2)Cl(2) (.0.5CH(2)Cl(2)), [Et(4)N][Tp*W(mu(3)-S)(mu-S)(2)(CuNCS)(2)].ClCH(2)CH(2)Cl (.ClCH(2)CH(2)Cl), [Et(4)N](2)[Tp*W(mu(3)-S)(3)(CuNCS)(3)(mu(3)-Br)].1.5aniline (.1.5aniline), and {[Et(4)N][Tp*W(mu(3)-S)(3)(Cu-mu-SCN)(3)(Cu-mu(3)-NCS)]}(n) (). Compounds were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, and single-crystal X-ray crystallography. The cluster anion of contains a [WS(2)Cu] core formed by addition of one CuNCS group onto the [Tp*WS(3)] species. The cluster anion of has a butterfly-shaped [WS(3)Cu(2)] core constructed by addition of two CuNCS groups onto the [Tp*WS(3)] species. The cluster dianion of consists of a cubane-like [Tp*WS(3)Cu(3)(mu(3)-Br)] core assembled by addition of three CuNCS groups onto the [Tp*WS(3)] species followed by filling a mu(3)-Br into the void of the incomplete cubane-like [Tp*WS(3)(CuNCS)(3)] fragment. has a 2D cluster-supported layer network in which each [Tp*WS(3)Cu(3)] core acting as a pyramidal 3-connecting node interconnects with the [Cu(NCS)(4)] units through thiocyanate bridges. In addition, the third-order nonlinear optical (NLO) performances of in DMF were also investigated by Z-scan techniques.

[Raman spectroscopic investigation on the interactions between liver Cancer cells (SMMC-7721) and fufang Luxiancao particles].

Luxiancao is a new medicine for liver cancer, and is purely natural botanical It has good curative effects and few side effects. The curative mechanism of Luxiancao is unknown. In the present paper, the authors used a 514. 5 nm laser to measure the changes in the Raman spectrum of liver cancer cells (SMMC-7721) treated by Luxiancao at different concentrations. The study can help us know more about the mechanism, efficiency and side effects of Luxiancao. The results show that significant changes were observed in the cells' Raman spectra after reacting with Luxiancao. The intensities at 785 and 1 092 cm(-1), corresponding to DNA phosphate backbone vibration, were reduced; and the Raman bands for the bases A and G at 1 312 and 1585 cm(-1) also decreased, indicating that Luxiancao may be inserted in DNA bases and influence the DNA replications, resulting in the reduction in DNA content and breaking of the DNA strands. Besides, the intensity of 1 360 cm(-1), belonging to Trp, decreased gradually and disappeared in the end, indicating the Trp of cancer cells began to be exposed when adding in Luxiancao. The bands at 1 004 cm(-1) for Phe and 1 656 cm(-1) for proteins alpha-helix also decreased, suggesting that there were changes in the structure of protein and circumstance of amino acid. Moreover, the effects on cancer cells were enhanced gradually with the HCPT concentration increasing. Since a Raman spectrum is a chemical fingerprint of a sample, the different concentration dependent changes in the Raman spectra of individual cells due to reacting with Luxiancao can overcome the limitations of other detection systems used for quantitative and qualitative analysis of the drug.