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Organic compounds of actinyls and their bonding features have attracted extensive attention in nuclear waste separation due to their characteristics of separating fission products. Herein, detailed studies on the binding sites of [AnO2(COOH) n (H2O) m ]2-n (An = U, Np, Pu, and Am; n = 1-3; m = 0, 2, 4; 2n + m = 6) complexes toward Cs are predicted by calculation, and their electronic excitation characteristics were illustrated, providing theoretical supports for the design of Cs adsorbents. The quantum theory of atom in molecules and electron localization function have been implemented to analyze the chemical bonding characterization. The covalent character of An-OC bonds become weaker with increasing COOH- ligands, and the covalent interaction in An-OC bonds is more obvious than that in An-OH bonds. Total and partial population density of state suggest that the 2p orbits of O have more significant contribution in the low-energy region atoms and the 6d/5f orbits of An have more significant contribution in the high-energy region. The Cs+ best adsorption site on [UO2(COOH)2(H2O)2] and [UO2(COOH)3]- is the adjacent oxalates, and the [UO2(COOH)3]- complexes have better adsorption capacity. Besides, the electronic excitation characteristics of Cs+ adsorption on the UO2(COOH)2(H2O)2 complex were analyzed by the UV-vis spectrum and hole-electron distribution.

The light-induced frequency shift (LIFS) of ultracold molecular ro-vibrational levels originates from the strong coupling of the atomic-scattering state and the bound-molecular state. In this paper, we present our experimental determination of the LIFSs of the lowest vibrational levels (ν = 0, 1) in the purely long-range $$0_g^-$$ state of ultracold cesium molecules. A high-resolution double photoassociation spectroscopy is developed, which serves as frequency ruler to measure the frequency shifts of the lowest molecular levels for Cs2. The experimental results are qualitatively consistent with the theoretical expectations.

Highlights • ZnO/ZnS nanostructures with type-II heterojunction are successfully synthesized. • Heterojunction nanotube exhibits better sonophotocatalysis than nanorod. • Effect of morphology on piezoelectric is experimentally and simulatively studied. • Morphology engineering can affect sonophotocatalysis through turning piezoelectric., Sonophotocatalysis is one of the most significant outcomes of the exploration of the interaction between piezoelectric field and charge carriers, which exhibits potential applications in dye degradation, water splitting, and sterilization. Although several heterojunction catalysts have been applied to improve the sonophotocatalytic capability, the importance of the morphology on the sonophotocatalytic capability has not been emphasized. In this study, brush-like ZnO nanorod arrays are synthesized on a stainless-steel mesh and subsequently vulcanized into ZnO/ZnS core–shell nanorod arrays to investigate the sonophotocatalytic capability of the heterojunction. The sonophotocatalytic capability increases from 25.1% to 45.4% through vulcanization. Afterward, the ZnO/ZnS nanorods are etched to ZnO/ZnS nanotubes without affecting the crystallography and distribution of the ZnS nanoparticle shell, further improving the capability to 63.3%. The improvement can be ascribed to the coupling effect of the enhanced piezoelectric field and the reduced migration distance, which suppresses the recombination of photoexcited electron–hole pairs while transforming the morphology from nanorod to nanotube, as proven by the electron spin resonance test and numerical simulations. This study explores a novel approach of morphology engineering for enhancing the sonophotocatalytic capability of heterojunction nanoarrays.

We present experimental and theoretical results on the measurements of the oscillation frequency in a dipole trap based on the spin current in a sodium spinor Bose–Einstein condensate. The spin current is induced under different magnetic field intensities. The oscillation of the spin components in the dipole trap is strongly enhanced by a radio frequency pulse. Both theoretical analysis and experimental results demonstrate that this method can be used to efficiently measure the trap frequencies. Since this mechanism is independent of atomic species, this study is promising to be extended to rubidium and other optical-trappable quantum gases.

Photoassociation of ultracold Cs atoms is reported in magneto-optical trap with the modulation technique. Trap loss spectroscopy of the ultracold Cs2 molecules has been obtained experimentally. Spectroscopy data are expended to the red detuned of 70 cm-1 below the 6S1/2+6P1/2 dissociation limit. Several new low lying vibrational levels belongs to the 0u+ and 1g states are identified and analyzed. The long range molecular coefficients C3 for the 0u+ and 1g states are obtained, and the corresponding empirical potential curves are derived with the spectroscopy data.

We report an accurate experimental determination of rotational constants of the lowest vibrational levels in the purely long-range state of ultracold cesium molecules (Cs 2 ). We engineer a precise reference of the frequency difference through double photoassociation spectroscopy (PAS). The PAS for the lowest vibrational levels, v=0–3, has been obtained with an enhanced sensitivity and accuracy, according to which the binding energies have been corrected. As deduced from the reference, the frequency intervals between neighboring rotational levels are fitted to a non-rigid rotor model, thus the rotational constants are precisely obtained. The experimental results show good agreement with theoretical expectations.

The objective of this study is to improve the bioavailability of genistein by encapsulation with polyethylene glycol-polylactic acid (PEG-PLA) copolymers. Genistein micelles (GMs) prepared using a modified emulsion-evaporation method were more stable than those made with the original method. The effect of polyvinyl alcohol, Tween 80, sonication time, PEG-PLA/genistein ratio, and organic phase (acetone)/H2O ratio on the size, polydispersity index, encapsulation efficiency, and drug loading efficiency of GMs was investigated. GMs were obtained and characterized under optimal experimental conditions. For long-term storage, GMs were lyophilized by freeze drying with trehalose to produce genistein lyophilized powder (GLP). The analysis of GLP by Fourier-transform infrared spectroscopy and differential scanning calorimetry showed that genistein was successfully incorporated into the micellar structure. In vitro release experiments revealed that the incorporation of genistein into PEG-PLA copolymers significantly improved its solubility and bioavailability. GLP was more potent in inhibiting the proliferation of HSC-T6 cells than genistein. Treatment with GLP at 10–20 μg/mL for 48 h significantly inhibited the protein expression of α-smooth muscle actin and collagen I in HSC-T6 cells compared with the control. These data demonstrated that the improved solubility and bioavailability of genistein in the form of GLP enhanced its antifibrotic effect in vitro.

Constructing heterojunction is a promising approach to enhance the piezo-photocatalytic performance of ZnO nanostructures. In this study, ZnO/ZnS heterojunction nanoarrays have been synthesized by facile vulcanizing surface of wurtzite ZnO nanorods into blende ZnS nanoparticles through hydrothermal method. Both the synthesized wurtzite ZnO nanorods and blende ZnS nanoparticles are piezoelectric semiconductors with wide band gaps. For degrading methyl blue solution under UV irradiation and ultrasonic sonication, it is found that both the piezocatalytic, photocatalytic and piezo-photocatalytic performances of ZnO/ZnS nanoarrays are much higher than those of pure ZnO. In addition, the piezo-photocatalytic degradation rate of ZnO/ZnS nanoarrays can be further increased by improving the ultrasonic power. The mechanism can be attributed to the synergetic effect of piezoelectric effect and heterojunction photocatalysis.

Direct Z-scheme heterojunction of ZnO/MoS2 nanoarray on Ni foam has been realized by flowing induced piezoelectric field for enhanced sunlight photocatalytic performances. The porous structure of Ni substrate can effectively induce applied deformation on nanorod arrays and generate built-in piezoelectric field by water flowing. Under sunlight irradiation for 50 min, the photocatalytic degradation efficiency of methyl orange is 50.6 %, and the degradation efficiency rapidly increases to 92.7 % under stirring-sunlight irradiation. The degradation rate increases with increasing stirring speed along an S-shaped relationship. In addition, the heterojunction photocatalyst also performs good repeatability in aqueous solution and even in alkaline solution. The role and amount of active radicals are investigated by radical scavenger experiments and electron spin resonance technique, indicating that only the amount of ∙ O H radicals can be significantly increased by flowing induced piezoelectric field. This interesting phenomenon can be attributed to that piezoelectric field converts Ⅱ-type heterojunction into Z-scheme configuration.

We report on a research of the loading of ultracold sodium atoms in an optical dipole trap, generated by two beams from a high power fiber laser. The effects of optical trap light power on atomic number, temperature and phase space density are experimentally investigated. A simple theory is proposed and it is in good accordance with the experimental results of the loaded atomic numbers. In a general estimation, an optimal value for each beam with a power of 9 W from the fiber laser is achieved. Our results provide a further understanding of the loading process of optical dipole trap and laid the foundation for generation of a sodium Bose–Einstein condensation with an optical dipole trap.

We propose a new transparency mechanism, which is based on photoassociation (PA) laser intensity induced transitional frequency shift for ultracold cesium molecules formed in PA scheme. The PA laser intensity is supposed to change before the atom-molecule resonance. Thus, a remarkable transparent effect for PA laser is expected to appear in the vicinity of original resonant transitional line, where the variation of PA laser intensity induces the shift of the excited molecular levels. The mechanism is different from electromagnetically induced transparency effect and interesting for further research on the scattering length for cesium atomic condensate.

We report on a quantitative experimental determination of the rotational constants for the high-lying vibrational levels of the ultracold pure long-range Cesium molecules formed via photoassociation. The scheme relies on a precise reference of frequency difference in a double photoassociation spectroscopy, which is induced by two laser beams based on an acoustic-optical modulator. The rotational constants are obtained by fitting a nonrigid rotor model into the frequency intervals of the neighboring rotational levels deduced from the reference.

We demonstrate nonlinear Fano effect in ultracold atom-molecule system composed of Photoassociation (PA) near a narrow d -wave Feshbach resonance for Cs atoms in the hyperfine state F = 3, mF = 3. A series of PA spectra of ultracold Cs atoms trapped in a crossed dipole trap are recorded near the Feshbach resonance. We measure PA rate as a function of magnetic field and clearly find Fano effect with characteristically asymmetric line shapes. Meanwhile, we investigate variations of spectral broadening and shifts as magnetic field around the Feshbach resonance. Our results also show Fano effect has a great effect on both spectral broadening and slope of spectral shift. We develop a nonlinear Fano theory based on magnato-optical quantum interferences in this ultracold atom-molecule system. The theory provides a remarkable agreement with our experimental results.

Droplet formation in a wide-type microfluidic T-junction was studied using the computational fluid dynamics (CFD) method. Two distinct regimes of droplet formation were confirmed: dripping and jetting; and, at both regimes, droplet size decreases with an increase in capillary number. CFD simulation demonstrated that droplet formation in the T-junction can be divided into three steps: droplet emergence and growing up; separation with the disperse phase; and detachment from the channel wall. The wettability of the channel wall significantly affects the process of droplet detachment from the channel wall; also, the simulation clearly showed that droplets can be formed only when the continuous phase fluid preferentially wets the channel wall, that is, its contact angle on the wall is smaller than 90°. Finally, the CFD study verified that the disperse phase flow rate can significantly affect the droplet size as well as the mechanism of droplet formation.

In this paper, a high sensitive photoassociation spectroscopy of cesium molecular 0 g - long-range state close to the 6S1/2 + 6P3/2 dissociation limit is reported based on modulated ultracold cesium atoms in a dark-spot magneto-optical trap. The atoms are mainly populated in hyperfine level F = 3 which is called dark hyperfine state, where atoms are not interacting with trapping light and not influenced by interatomic force. We employed lock-in detection technique by modulating fluorescence of cold atoms to obtain high sensitivity spectroscopy. The signal-to-noise ratio of spectroscopy in dark SPOT is up to 115.6, which is remarkably improved. Our technical proved to be a robust tool for effectively improving the signal-to-noise ratio of atom loss spectroscopy.

We report on the production of ultracold heteronuclear NaCs* molecules in a dual-species magneto-optical trap through photoassociation. The electronically excited molecules are formed below the Na (3S1/2) + Cs (6P1/2) dissociation limit. 12 resonance lines are detected using trap-loss spectroscopy based on a highly sensitive modulation technique. The highest observed rovibrational level exhibits clear hyperfine structure, which is detected for the first time. This structure is simulated within a simplified model consisting of 4 coupled levels belonging to the initially unperturbed Hund’s case “a” electronic states, which have been explored in our previous work that dealt with the Na (3S1/2) + Cs (6P3/2) asymptote [W. Liu et al., Phys. Rev. A 94, 032518 (2016)].

Two series of diorganotin(IV) complexes with dihalogenobenzohydroxamate ligands (substituents = 2,4-Cl2, 2,4-F2, 3,4-F2, 2,5-F2, 2,6-F2), formulated as [R2Sn(HL)2] (a), and the arylhydroxamato/arylcarboxylato mixed-ligand complexes [R2Sn(HL)(L′)] (b), were prepared and characterized by FT-IR, 1H, 13C and 119Sn NMR spectroscopies, elemental analyses and melting point measurements. X-ray diffraction analysis was also carried out for the complex [Me2Sn{3,4-F2C6H3C(O)NHO}2], 1a. These compounds exhibit in vitro cytotoxic activities towards human leukemic promyelocites HL-60, BGC-823, BEL-7402 and KB cell lines which, in some cases, are identical to, or even higher than, that of cisplatin. The type, position and number of the X substituents in the phenyl ring play a role in the cytotoxic activity, and complex 8a, with its 2,6-difluorobenzohydroxamato ligand, is highly active against all tumor cells. A tentative structure–activity relationship is also described. Copyright © 2007 John Wiley & Sons, Ltd.

New ro-vibrational structures of cold Cs2 in the 0u(+) state near the asymptote 6S1/2 + 6P1/2 are resolved. The variation of the rotational constants shows that the related energy spectra are strongly perturbed. An analysis of new data along with the empirical and theoretical information available from other sources is performed. For this purpose the model of spin-orbit coupling of the Hund's case (a) states A(1)Σu(+)∼b(3)Πu proposed by Bai et al. [Phys. Rev. A 83, 032514 (2011)] is extrapolated to the dissociation limit, and the parameters of the extrapolation are fitted from the near-dissociation experimental data.

We investigate an effective control of the laser-induced frequency shift of ultracold cesium molecules formed by photoassociation (PA) in a magnetically levitated crossed dipole trap via an external magnetic field. A series of molecular PA spectra have been measured with increasing the PA laser intensity at different bias fields. We find that the slope of laser-induced frequency shift is strongly dependent on the external magnetic field: the slope can be increased up to a maximum of ∼6 times compared with a slope without an external magnetic field. A qualitatively theoretical explanation has been offered by considering the external magnetic field that can be used to manipulate the interaction between ultracold atoms.

We report a detailed study of effective magnetically levitated loading of cold atoms in a crossed dipole trap: an appropriate magnetic field gradient precisely compensates for the destructive gravitational force of the atoms and an additional bias field simultaneously eliminates the antitrapping potential induced by the magnetic field gradient. The magnetic levitation is required for a large-volume crossed dipole trap to form a shallow but very effective loading potential, making it a promising method for loading and trapping more cold atoms. For cold cesium atoms in the $F=3, mF=3$ state prepared by three-dimensional degenerated Raman sideband cooling, a large number of atoms $\ensuremath{\sim}3.2\ifmmode\times\else\texttimes\fi{}{10}^{6}$ have been loaded into a large-volume crossed dipole trap with the help of the magnetic levitation technique. The dependence of the number of atoms loaded and trapped in the dipole trap on the magnetic field gradient and bias field, respectively, is in good agreement with the theoretical analysis. The optimum magnetic field gradient of 31.13 G/cm matches the theoretical value of 31.3 G/cm well. This method can be used to obtain more cold atoms or a large number of Bose-Einstein condensation atoms for many atomic species in high-field seeking states.

When R2SnCl2 (R = Me, nBu) reacted with substituted benzohydroxamic acid (substituent = 4-F; 2,4-Cl2; 2,5-F2) and potassium hydroxide in aqueous methanol solution, two types of condensation products could be obtained, depending on the molar ratio R2SnCl2/RCONHOH/KOH. When a 1:1:2 molar ratio was used, 1:1 alkyltin hydroxamates {(n-C4H9)2Sn[4-FC6H4C(O)NO]}n (1) and {(CH3)2Sn[2,5-F2C6H3C(O)NO]}n (2) were formed. When a 1:2:2 ratio was used, another two unexpected 2:3 alkyltin hydroxamates, {(CH3)4Sn2[(2,4-Cl2C6H3C(O)NHO)2][2,4-Cl2C6H3C(O)NO]}n (3) and {(n-C4H9)4Sn2[(4-FC6H4C(O)NHO)2][4-FC6H4C(O)NO]}n (4), were obtained. All these complexes were characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectra and X-ray diffraction analysis. The results indicated overall (Z)-iminol coordination mode in the hydroximic tautomeric form for 1 and 2, and keto-iminol mixed-coordination mode including both in (Z)-hydroxamic and -hydroximic tautomeric forms for 3 and 4. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

We report enhanced three-dimensional degenerated Raman sideband cooling (3D DRSC) of caesium (Cs) atoms in a standard single-cell vapour-loading magneto-optical trap. Our improved scheme involves using a separate repumping laser and optimized lattice detuning. We load $1.5 \times 10^7$ atoms into the Raman lattice with a detuning of -15.5 GHz (to the ground F = 3 state). Enhanced 3D DRSC is used to cool them from 60 $\mu$K to 1.7 $\mu$K within 12 ms and the number of obtained atoms is about $1.2 \times 10^7$. A theoretical model is proposed to simulate the measured number of trapped atoms. The result shows good agreement with the experimental data. The technique paves the way for loading a large number of ultracold Cs atoms into a crossed dipole trap and efficient evaporative cooling in a single-cell system., Comment: 9 pages, 4 figures. Accepted in Laser Physics Letters

Laser cooling of atoms is the basis of researches on ultracold atoms and molecules. It is of great importance in the study of precision measurement and quantum simulation, etc. In order to obtain ultracold cesium atomic sample with a lower temperature and a higher density, as the starting point to create ultracold cesium ground state molecules, we demonstrate in this article a method which effectively overcomes the heating from the reabsorption of scattered light in magneto-optical trap to further reduce the ultracold atomic temperature by loading atoms into a 3D optical lattices. Based on obtaining the ultracold Cs atoms in a standard magneto-optical trap, we use the compressed magneto-optical trap technology to increase ultracold Cs atomic density. Efficient loading of ultracold Cs atoms is achieved by 3D optical lattices which constructed by four lasers; the temperature of the atoms is measured by time-of-flight method. We observed the cooling result that the temperature drops from ~60.0 μK to ~11.6 μK. We also explore the dependence of the atom numbers in the lattice on the frequency of lattice lasers, and lead to the conclusion that the loading rate of the optical lattices reaches its maximum when the lattices laser’s detuning is –15.5 GHz. In the meantime, this paper investigates the use of optical lattice to suppress the heating of the ultracold atoms due to the radiation photons, in this sense, our research has far-reaching significance. Our scheme is advantageous due to its relaxed starting temperature requirement, meaning that 3D DRSC can be directly accomplished in a standard single cell vapour-loaded MOT without reliance on any additional devices such as a Zeeman slower.

The impacts on the sorption of phenanthrene (PHE) onto single-walled carbon nanotubes (SCNT) by loading of dissolved organic matter (DOM) fractions with different molecular weights (MWs) were studied. Moreover, the influence of contact time on the sorption capacity of DOM-modified SCNT was evaluated for the first time. Preloading of DOM on SCNT for 2 days led to a reduction in PHE sorption and the nonlinearity of the sorption isotherm; however further increasing the contact time between the DOM and SCNT from 2 days to 20 days enhanced the sorption capacity, and the sorption nonlinearity increased also. This is due to the transferring of DOM molecules from the external surface to interstitial channels trapped in SCNT particles, restoring the sorption sites. The loading of DOM fraction with MWs larger than 14000 Da (DOM14000) brought a stronger suppression of PHE sorption by SCNT compared to smaller ones (DOM1000 and DOM1000–14000), with the Freundlich nonlinear index n increasing from 0.236 to 1.093 and the Freundlich affinity coefficient log KF decreasing from to 7.34 to 4.57. These are similar to the sorption characteristics of DOM14000, suggesting a complete coverage of the SCNT by DOM14000 molecules. Though the loading of DOM fractions with smaller MWs made SCNT more polar, the reduction in PHE sorption on DOM-preloaded SCNT was limited due to their lesser sorbed amount and smaller molecular size.

We present a controllable three-dimensional fluorescence modulation technique for the high sensitive trap loss detection of ultracold molecules. The lowest vibrational levels (v = 0 and 1) of the pure long-range state 0(-)(g) (6S(1/2) + 6P(3/2)) of a cesium molecule are detected directly with high rotational resolution. Our technique proved to be a robust tool for effectively improving the detection sensitivity of trap loss spectroscopy.

Aim of the study This study was aimed to evaluate the neuroprotective and anti-aging activity of extracts in Caenorhabditis elegans from the roots and leaves of Damnacanthus officinarum Huang to provide the pharmacological basis in traditional medicine. Materials and methods Investigations on the neuroprotective and lifespan activity were carried out, which were observed by utilizing the following models: observing the worms’ chemosensory behavior test based on the aversion index in the assay plate, neuroprotective activity of nematode by evaluating the ASH neuron survival and lifespan test in C. elegans . Results It has been shown that the ethanol, n -butanol and aqueous extracts in the roots possessed significantly neuroprotective effect both in chemosensory behavior test and ASH neuron survival model. The same extracts in the leaves showed similar activities in two models, but have less potency revealing by the data. Four candidate extracts, possessing excellent neuroprotective activity, extend lifespan in C. elegans . The n -butanol extracts in the root part showed best efficacy among them. Conclusion The results show the n -butanol and aqueous extracts are the major pharmacological plant extracts. Moreover, the neuroprotective and lifespan-extension activity effects of root extracts are superior to leave extracts, supporting the traditional application of above-ground parts of DOH in treating various diseases associated with brain disorders and anti-aging.

Series of polynuclear diorganotin(IV) complexes with di-halogenbenzohydroxamate ligands (substituents = 2,4-Cl 2 , 2,4-F 2 , 3,4-F 2 , 2,5-F 2 , 2,6-F 2 ), formulated as the polymeric [R 2 SnL] n a (1:1) and the tetranuclear [R 4 Sn 2 (HL) 2 (L)] 2 b (2:3) (HL = arylhydroxamate), were prepared and characterized by FT-IR, 1 H, 13 C, 119 Sn NMR spectroscopies, elemental analyses and melting point measurements. X-ray diffraction analyses were also carried out for the representative complexes [Me 2 Sn{2,4- F 2 C 6 H 3 C(O)NO}] n 2a and [ n -Bu 4 Sn 2 {2,4- F 2 C 6 H 3 C(O)NHO} 2 {2,4-F 2 C 6 H 3 C(O)NO}] 2 1b and show that the ligated mono- and di-basic forms, HL and L, of the arylhydroxamic acid (H 2 L) display the ox a mic and ox i mic tautomeric forms, respectively. These compounds exhibit in vitro cytotoxicities toward human leukemic promyelocites HL-60, BGC-823, BEL-7402 and KB cell lines which, in some cases, are identical to, or even higher than, that of “cisplatin”. The polymeric diorganotin/hydroxamato complexes a containing the long carbon chain butyl ligands are the most active ones, and the dependence of the antitumor activity of the complexes on various factors, namely the nuclearity, the organic ligand, the type, position and number of the X ring substituents, is also discussed.

We report on new observations of the photoassociation spectroscopy of ultracold cesium molecules using a highly sensitive detection technique and a combined analysis with all observed electronic states. The technique is achieved by directly modulating the frequency of the trapping lasers of a magneto-optical trap. New observations of the Cs2 0g(-), 0u(+), and 1g states at the asymptotes 6S1/2 + 6P1/2 and 6S1/2 + 6P3/2 are reported. The spectral range is extended to the red detuning of 112 cm(-1) below the 6S1/2 + 6P3/2 dissociation limit. Dozens of vibrational levels of the ultracold Cs2 0g(-), 0u(+), and 1g states are observed for the first time. The available experimental binding energies of these states are analyzed simultaneously in a framework of the generalized LeRoy-Bernstein theory and the almost degenerate perturbation theory by Marinescu and Dalgarno [Phys. Rev. A: At., Mol., Opt. Phys. 52, 311 (1995)]. The unique atomic-related parameter c3 governing the dispersion forces of all the molecular states is estimated as (10.29 ± 0.05) a.u.

In the title compound, C7H5F2NO2, the hydroxyl group is trans to the difluoro­phenyl group with respect to the C—N bond. The mol­ecules are linked into chains of rings parallel to [100] by a combination of O—H⋯O and N—H⋯O hydrogen bonds.

High-resolution photoassociation spectroscopy is reported using a modulation spectroscopy technology in a cesium atomic magneto-optical trap. The two lowest vibrational levels have been experimentally observed which have been theoretically predicted in [Phys. Rev. A 75 052501 (2007)]. A new potential curve is obtained by using the Rydberg—Klein—Ress method with a well depth of −82.384 ± 0.026 cm−1, which is deeper than the result of previous experiment (−77.909 cm−1) and the theoretical prediction (−81.6445 cm−1).

In this paper, ultracold cesium molecules are formed through photoassociation technology, which is carried out in a magneto-optical trap. High resolution photoassociaion spectra with the rotational progressions up to J = 7 are obtained. Three rovibrational levels of the long-range 0u+ state of Cs2 below the (6S1/2 + 6P1/2) dissociation limit are specifically investigated. By fitting their binding energy intervals to the non-rigid rotational model, the rotational constant of the long-range 0u+ state is determined. A proportional dependence of the value of the rotational constant on the vibrational quantum number is demonstrated.

We report on a quantitative experimental determination of the laser-induced frequency shift rate of the ultracold cesium molecules formed via photoassociation (PA) by means of the trap loss measurement of the losses of trapped atoms in a standard magneto-optical trap. The experiment was directly performed by varying the photoassociation laser intensity without any additional frequency monitor technologies. Our experimental method utilized dependences of the losses on the laser-induced frequency shift rate based on the conditions of the identified photoassociation spectral shape. We demonstrated that the method is sensitive enough to determine small frequency shifts of rovibrational levels of ultracold cesium molecules.

We propose a technique to precisely measure the line width of the photoassociation spectra of the excited cesium molecule by using a frequency shifter to generate two laser beams with a precise frequency difference. A series of photoassociation (PA) spectra are recorded with two laser beam induced molecular lines, whose peak separation serves as an accurate frequency ruler to measure the line width of the PA spectra. The full width half maximum line width was studied as a function of PA laser intensity. The extrapolated value at zero laser intensity is (34.84 ? 0.22) MHz. By analyzing other broadening mechanisms, a value of (32.02 ? 0.70) MHz was deduced. It is shown that this scheme is inexpensive, simple, robust, and is promising for applications in a variety of other atomic species.

We have produced ultracold polar RbCs molecules via photoassociation starting from laser-cooled 85Rb and 133Cs atoms in a dual-species, forced dark magneto-optical trap. The formed electronically excited RbCs* molecules correlated to the Rb(5S1/2) + Cs(6P1/2) dissociation limit are observed by trap loss spectroscopy. Following the decay of these excited RbCs* molecules, the formed ground state molecules are directly ionized by a two-photon single-color pulse dye laser, which is a new ionization mechanism for ground state RbCs molecules and thence detected by time-of-flight mass spectroscopy.

We experimentally present a technique for sensitively determining the laser-induced frequency shifts of the long-range molecular vibrational and rotational levels. The scheme relies on an optical frequency shifter, leading to two laser beams with a precise and adjustable frequency interval. A series of photoassociation spectra are recorded with both beams inducing molecular lines, whose peak separation provides an accurate frequency ruler to measure the frequency shifts of cesium molecular levels, which have not yet been observed in previous reports. The data are compared to theoretical predictions and show a good agreement.

In the title compound, C22H16F3NO7S, the two benzene rings are almost perpendicular, the dihedral angle between their mean planes being 87.1 (1)°. The terminal O atom of the benzoate moiety is disordered over two positions with site occupancies of 0.244 (15) and 0.756 (15). The crystal structure is stablized by two types of weak intermolecular C—H...O hydrogen bonds.