CAJ | 학술논문

卟啉类化合物是一类重要的光化学材料，其衍生物特殊的光电特性在各个领域中得到了广泛的应用。利用密度泛函理论（DFT ）研究了（free base porphyrin ， FBP ）及其异构体（neo-confused porphyrin ， NECP）和（n-confused porphyrin ，NCP）三种卟啉环的几何结构和分子轨道能级。采用TDDFT方法计算真空和溶剂场极化连续模型下三者的吸收光谱。计算表明由于N原子位置变化，FBP ，NECP和NCP在Soret带和Q带两个特征吸收峰也有不同。按FBP ，NECP和NCP顺序，分子轨道能级LUMO依次降低，HOMO轨道依次升高，从而造成吸收光谱红移。HOMO 和 HOMO -1轨道能级的分裂造成了 FBP和 NECP的Soret带的多个吸收峰，而NCP的LUMO和LUMO＋1的能级差与其HOMO和HOMO-1能级差几乎相等造成Soret带只有一个最高吸收峰。计算结果表明不同溶剂（苯、氯仿、乙腈和水）条件下三者的Soret带和Q带特征吸收峰均有显著变化。为此重点讨论了 N 原子位置的变化及在不同性质溶剂下 FBP ，NCP和NECP三类化合物Soret带/Q带吸收光谱性质的变化规律和机理。
계람류화합물시일류중요적광화학재료，기연생물특수적광전특성재각개영역중득도료엄범적응용。이용밀도범함이론（DFT ）연구료（free base porphyrin ， FBP ）급기이구체（neo-confused porphyrin ， NECP）화（n-confused porphyrin ，NCP）삼충계람배적궤하결구화분자궤도능급。채용TDDFT방법계산진공화용제장겁화련속모형하삼자적흡수광보。계산표명유우N원자위치변화，FBP ，NECP화NCP재Soret대화Q대량개특정흡수봉야유불동。안FBP ，NECP화NCP순서，분자궤도능급LUMO의차강저，HOMO궤도의차승고，종이조성흡수광보홍이。HOMO 화 HOMO -1궤도능급적분렬조성료 FBP화 NECP적Soret대적다개흡수봉，이NCP적LUMO화LUMO＋1적능급차여기HOMO화HOMO-1능급차궤호상등조성Soret대지유일개최고흡수봉。계산결과표명불동용제（분、록방、을정화수）조건하삼자적Soret대화Q대특정흡수봉균유현저변화。위차중점토론료 N 원자위치적변화급재불동성질용제하 FBP ，NCP화NECP삼류화합물Soret대/Q대흡수광보성질적변화규률화궤리。
Porphyrin is an important class of photochemical materials ,which has been widely used in various fields .Computa-tional investigations into the ground state structures and orbital energy levels of free base porphyrin (FBP) ,neo-confused por-phyrin (NECP) and N-confused porphyrin (NCP) were performed with density functional theory (DFT ) .Absorption spectra were calculated at TD-B3LYP/6-31+G(d) .Degeneracy of HOMO and HOMO -1 is lost ,which would account for the shoulder peaks about the most intense transitions of FBP and NECP .Following FBP ,NECP and NCP order ,the orbital energy level (OEL) of LUMO decreases while the OEL of HOMO increases ,which lead to the red shift of adsorption spectra .The energy difference between LUMO and LUMO+1 is almost the same as the difference between HOMO and HOMO -1 ,which would ac-count for the only most intense transition of NCP .Solvent effect on ground state structures and absorption spectra was also in-vestigated .The data shows that the character peak of Soret band and Q band changes in different solvent (benzene ,chloroform , acetonitrile and water ) .So we further focus on discussing the N atom position and solvent effects on the energy level and Soret/Q bands of FBP ,NCP and NECP ,as well as clarifying its variation regularity and mechanism .