基于密度泛函叶绿素a分子活性的量子化学计算  

Quantum Chemical Calculation of the Activity of Chlorophyll-a Molecule by DFT

作　　者：程江维[1,2] 湛敏[1,2] 张云怀[1,2] 

机构地区：[1]重庆大学化学化工学院,重庆400030 [2]重庆市三峡库区自然生态系统结构与系统模拟重点实验室,重庆400030

出　　处：《中国细胞生物学学报》2011年第4期372-378,共7页Chinese Journal of Cell Biology

基　　金：国家自然科学基金(No.20877105);重庆大学"211工程"三期建设研究生开放实验室支持项目(No.S-09013);重庆大学大学生创新基金资助项目~~

摘　　要：在液相环境下,根据量子化学密度泛函(DFT)的B3LYP泛函在6-31G基组水平的计算结果,从叶绿素a分子的光谱特性、特征基团对前线轨道能量贡献率、激发态、Mulliken电荷分布等量化参数分析比较了其各特征基团的生物活性及吸收波长。结果表明:叶绿素a分子中的5个活性基团中,C(33)、O(34)所组成的酮羰基活性最强,卟啉环的活性次之,C(36)位置上的酯羰基和C(13)位置上的酯羰基及共轭碳碳双键的活性较弱;在发生HOMO→LUMO跃迁后,卟啉环转移的电荷变化总量为0.00012。而酮羰基得到的电荷变化,总量为-0.00062。The bioactivity and absorption wavelength of the characteristic groups of chlorophyll-a mol- ecule was compared according to the spectral characteristic, contribution rates of characteristic groups to the energy of frontier orbits, excited states, Mulliken atomic charges and other quantization parameters which were calculated using the B3LYP flavor of density functional theory （DFT） with the 6-31G basis set in solvents. The results show that in the five characteristic groups of chlorophyll-a molecule, the activity of the ketone composed of C（33） and O（34） is the strongest, the porphyrin ring take the second place, the ester carbonyl in C（13） and C（36） the conjugated double bond own the weaker activity. After the transition of HOMO to LUMO, the charges transfer total quantity of the porphyrin ring are 0.00012 and the charges transfer total quantity of the ketone are -0.00062.

关 键 词：叶绿素A 密度泛函 前线轨道贡献率 活性基团 

分 类 号：Q945[生物学—植物学]