23 research outputs found
Corrigendum to: The TianQin project: current progress on science and technology
In the originally published version, this manuscript included an error related to indicating the corresponding author within the author list. This has now been corrected online to reflect the fact that author Jun Luo is the corresponding author of the article
Potential Energy Surface for Large Barrierless Reaction Systems: Application to the Kinetic Calculations of the Dissociation of Alkanes and the Reverse Recombination Reactions
The isodesmic reaction
method is applied to calculate the potential
energy surface (PES) along the reaction coordinates and the rate constants
of the barrierless reactions for unimolecular dissociation reactions
of alkanes to form two alkyl radicals and their reverse recombination
reactions. The reaction class is divided into 10 subclasses depending
upon the type of carbon atoms in the reaction centers. A correction
scheme based on isodesmic reaction theory is proposed to correct the
PESs at UB3LYP/6-31+G(d,p) level. To validate the accuracy of this
scheme, a comparison of the PESs at B3LYP level and the corrected
PESs with the PESs at CASPT2/aug-cc-pVTZ level is performed for 13
representative reactions, and it is found that the deviations of the
PESs at B3LYP level are up to 35.18 kcal/mol and are reduced to within
2 kcal/mol after correction, indicating that the PESs for barrierless
reactions in a subclass can be calculated meaningfully accurately
at a low level of <i>ab initio</i> method using our correction
scheme. High-pressure limit rate constants and pressure dependent
rate constants of these reactions are calculated based on their corrected
PESs and the results show the pressure dependence of the rate constants
cannot be ignored, especially at high temperatures. Furthermore, the
impact of molecular size on the pressure-dependent rate constants
of decomposition reactions of alkanes and their reverse reactions
has been studied. The present work provides an effective method to
generate meaningfully accurate PESs for large molecular system
China's first step towards probing the expanding universe and the nature of gravity using a space borne gravitational wave antenna
In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few technologies tested on Taiji-1 are presented in this paper. Gravitational wave astronomy has opened the door to test general relativity and the effect of gravity in the Universe. The authors present the capabilities of an overlap between space gravitational wave detectors LISA and Taiji to constrain the Hubble constant to 0.5%, in 10 years, and what can be learned from the satellite pilot Taiji-1 launched in 2019.</p