9-芴酮C波段(4~8GHz)的转动光谱研究  

Rotational Spectroscopic Investigation on 9-Fluorenone at C-Band(4~8GHz)

作　　者：朱宇轩 杨霄宇 许昕荣 孙铭[1] 焦超 陈钱[1] 赵臻璐 陈维强 张鑫 刘洪新 ZHU Yu-xuan;YANG Xiao-yu;XU Xin-rong;SUN Ming;JIAO Chao;CHEN Qian;ZHAO Zhen-lu;CHEN Wei-qiang;ZHANG Xin;LIU Hong-xin(School of Electronic and Optical Engineering,Nan jing University of Science and Technology,Nanjing 210094,China;Beijing Spacecraft Manufacturing Co.Ltd.,Beijing 100094,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094 [2]北京卫星制造厂有限公司,北京100094

出　　处：《光谱学与光谱分析》2023年第6期1988-1992,共5页Spectroscopy and Spectral Analysis

基　　金：The National Natural Science Foundation of China(61627802,U1531107);the National Undergraduate Training Program for Innovation and Entrepreneurship(202010288046Z)。

摘　　要：9-芴酮是一种典型的含氧多环芳烃,是多环芳烃含羰基官能团的衍生物。含氧多环芳烃可以通过母体的直接光解或氧化而形成。9-芴酮是一种廉价、无毒的光催化剂,并且,通过时间分辨红外光谱和共振拉曼光谱可以将具有芳香羰基的9-芴酮作为研究光化学过程的原型分子。此外,由于9-芴酮是具有良好偶极矩的含氧多环芳烃,它有望作为射电天文学研究的重要目标,可以为确认深空多环芳烃的存在和揭示星际介质化学的内涵提供新的有效途径。目前,9-芴酮的纯转动光谱已逐渐在毫米波和微波范围内捕获。本次工作的目标是扩大9-芴酮在微波C波段(4~8 GHz)的实验室观测范围,进一步支持该分子和其他多环芳烃的天体物理研究。具体而言,在微波C波段,利用具有加热电磁阀气体脉冲喷嘴的宽带啁啾脉冲傅里叶变换微波光谱仪(cp-FTMW)对潜在的天体物理分子(9-芴酮)进行了研究。精确测量并归属了9-芴酮的27个全新的b类型纯转动跃迁。将实验数据与微波数据结合进行拟合,得到了9-芴酮的精确转动常数:A=1445.88473929(10)MHz,B=584.8716736(71)MHz,C=416.5506078(81)MHz。将测定的9-芴酮的光谱数据与各种理论计算和较高微波频率的实验结果进行了比较,此次结合拟合的转动常数的精度有了明显提高。可见,结合新测量数据与现有的微波区转动数据进行全局拟合分析,不仅有利于对基态结构的准确表征,也为此类分子的计算研究提供了基础。9-芴酮在振动基态下的新的转动跃迁的准确观测,也为在深空寻找多环芳烃分子提供了更多的光谱数据,将促进天体物理领域对多环芳烃的更广泛探索。这项工作也证明了cp-FTMW谱仪利用加热喷嘴检测超音速喷射膨胀中非挥发分子的能力。9-fluororenone is a typical oxygenated polycyclic aromatic hydrocarbon(PAH),derivative of PAHs containing carbonyl functional groups.Oxygenated PAHs can be formed by direct photolysis or oxidation of parent PAHs.As an inexpensive and nontoxic photocatalyst,9-fluororenone with such an aromatic carbonyl groupcan act as a prototype molecule for the study of photochemical process,mostly via the time-resolved infrared and resonance Raman spectroscopy.In addition,9-fluorenone could be a significant target of radio astronomy,because such oxygenated PAHs with decent dipole moments can provide a new and effective way to confirm the existence of PAHs in deep space and reveal the connotation of interstellar medium chemistry.The pure rotational spectra of 9-fluorenone have been gradually captured in the millimeter wave and microwave range.The present work aims is to expand the scope of laboratory observation of 9-fluorenone in the microwave C-band(4~8 GHz),and further support the astrophysical research of this molecule and other PAHs.Specifically,a potential astrophysical molecule,9-fluorenone,was investigated by a broadband chirped-pulse Fourier transform microwave spectrometer(cp-FTMW)with a heating solenoid valve gas pulse nozzle in the microwave C-band range.In this work,27 b-type pure rotational transitions of 9-fluorenone were newly measured and assigned.By combining with the microwave data fitting,we obtained precise rotational constants for 9-fluorenone with these values:A=1445.88473929(10)MHz,B=584.8716736(71)MHz and C=416.5506078(81)MHz.The measured rotational constants of 9-fluorenone were compared with various theoretical and experimental works.The measured spectroscopic parameters were compared with various theoretical and experimental works.The accuracy of rotational constants of this combined fitting is markedly improved.It can be seen that the combined fitting analysis is not only conducive to the accurate characterization of the ground state structure,but also provides the basis for the computational study o

关 键 词：天体物理学 多环芳烃 9-芴酮 转动光谱 微波 

分 类 号：O433.4[机械工程—光学工程]