In this study, we report a facile process for preparing a carbon-coated nanosized Li 4 Ti 5 O 12 nanoporous micro-sphere (CN-LTO-NMS) by a carbon pre-coating process combined with the spray drying method. The obtained material consists of a micron-size secondary sphere (10-20 mm) accumulated by carbon-coated nanosized primary particles ($200 nm). The nanosized primary particles and nanothickness carbon layer uniformly coated over the particles as well as the interconnected nanopores greatly improve its rate capability. As a consequence, the resulting sample delivers a reversible capacity of 160 mAhg À1 at 0.2 C, and shows remarkable rate capability by maintaining 79% of the capacity at 20 C (vs. 0.2 C), as well as excellent cycling stability with a capacity retention of 95% after 1000 cycles at 1 C rate (vs. 0.2 C).

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Ultracold single molecules have wide-spread potential applications, such as ultracold chemistry, precision measurements, quantum simulation and computation. However due to difficulty in full control of a complex atom-molecule system, the coherent formation of single molecules remains a challenge. Here we report an alternative route to coherently bind two atoms into a weakly bound molecule at MHz levels via coupling atomic spins to their two-body relative motion in a strongly focused laser with inherent polarization gradients. The coherent nature is demonstrated by long-lived atom-molecule Rabi oscillations. We further manipulate the motional levels of the molecules and measure the binding energy precisely. Our work opens the door to full control of all degrees of freedom in atom-molecule systems.

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The generation of magic number silica clusters [(SiO 2 ) n O 2 H 3 ]with n ) 4 and 8 by XeCl laser (308 nm) ablation of porous siliceous materials is reported. The production of magic cluster [(SiO 2 ) 4 O 2 H 3 ]can be enhanced by sample selection and experimental optimization so that it becomes the most prominent species in silica clusters. To study the structure of the magic cluster [(SiO 2 ) 4 O 2 H 3 ] -, we performed structural optimization for the neutral bare cluster (SiO 2 ) 4 , the neutral complex cluster (SiO 2 ) 4 O 2 H 4 , and the anionic cluster [(SiO 2 ) 4 O 2 H 3 ]at the HF/6-31G** level. It was found that the ground state of the bare silica tetramer has a linear chain structure whereas a pseudotetrahedral cage-like structural isomer of S 4 symmetry is most stable for the complex cluster (SiO 2 ) 4 O 2 H 4 . The stabilization of the three-dimensional (3D) structure can be attributed to the active participation of the O 2 H 4 group in chemical bonding during cluster formation. Our theoretical calculation and bonding analysis indicate that the magic number anionic cluster [(SiO 2 ) 4 O 2 H 3 ]might also take a pseudotetrahedral structure similar to (but with a different symmetry) that of the neutral precursor (SiO 2 ) 4 O 2 H 4 as the ground state in which the valence, coordination, and bonding characteristics of all the constituent atoms are nearly fully satisfied.