Laboratoire Charles Coulomb, University Montpellier, CNRS, Montpellier, France.
Advanced Materials Engineering and Modeling Group, Wroclaw University of Science and Technology, Wroclaw, Poland.
J Chem Phys. 2023 Aug 7;159(5). doi: 10.1063/5.0155821.
Nucleotides are organic compounds consisting of a phosphate group, a nitrogenous base, namely adenine (A), thymine (T), cytosine (C), or guanine (G), and a sugar, here deoxyribose. The magnitude of the first hyperpolarizability β of these four DNA nucleotides was determined in aqueous solution with the nonlinear optical technique of hyper rayleigh scattering under non resonant conditions at a fundamental wavelength of 800 nm. The smallest value is found to be 1.67 ± 0.15 × 10-30 esu for thymidine-5'-monophosphate and the highest is 1.76 ± 0.16 × 10-30 esu for 2'-guanosine-5'-monophosphate. Polarization resolved studies were also performed to question the symmetry of the first hyperpolarizability tensor and access the ratio of some elements of the first hyperpolarizability tensor. These experimental results were then compared to the theoretical values of these first hyperpolarizabilities obtained with the density functional theory at the level of the PCM-B3LYP/6-31G+(d) basis and taking into account the solvent.
核苷酸是由一个磷酸基、一个含氮碱基（即腺嘌呤（A）、胸腺嘧啶（T）、胞嘧啶（C）或鸟嘌呤（G））和一个糖（这里是脱氧核糖）组成的有机化合物。在非共振条件下，使用非线性光学技术超瑞利散射，在基本波长为 800nm 的条件下，测定了这四种 DNA 核苷酸的第一超极化率β的大小。结果发现，胸腺嘧啶-5'-单磷酸的第一超极化率β值最小，为 1.67 ± 0.15×10-30 esu，而 2'-鸟苷-5'-单磷酸的第一超极化率β值最高，为 1.76 ± 0.16×10-30 esu。还进行了偏振分辨研究，以质疑第一超极化率张量的对称性，并确定第一超极化率张量的某些元素的比值。然后，将这些实验结果与使用密度泛函理论在 PCM-B3LYP/6-31G+(d)基和考虑溶剂的水平下获得的这些第一超极化率的理论值进行了比较。
