Additivity of Group Contribution of Electron Correlation Energies in Linear Alkyl Fluorides

作者：Si Wei Jiang; Zhuo Shu Ping^*

来源：Acta Physico - Chimica Sinica, 2009, 25(6): 1131-1135.

• Correlation energy contributions
• Additivity of group contribution
• Linear alkyl fluoride

Correlation energy contributions of the -CH(3), -CH(2)- and -F functional groups in linear alkyl fluorides CH(3)(CH(2))(m)F (m=0-5) were calculated and studied at MP2-OPT2/6-311++G(d) level using Meld program. We found that with an increase in the number of intervening methylene groups in the studied systems, values of E(corr)(-F) and E(corr)(-CH(3)) decreased in the CH(3)(CH(2))(m)F (m=0-5) series. Values of E(corr)(-CH(2)-) are different in different positions with respect to the -F group in the system. The value of E(corr)(-CH(2)-) for the alpha position is larger than the values for methylene groups in other positions within the same system. The farther the -CH(2)- is from the -F group in the molecule, the smaller the value of E(corr)(-CH(2)-) is in CH(3)(CH(2))(m)F (m=1-5) systems. We predict that with an increase in the number m in the system, values of E(corr)(-CH(2)-), which are those of -CH(2)- groups relatively far from the terminal -F group, would converge to the value of a "standard" -CH(2)- group. This E(corr)(-CH(2)-) value is transferable between CH(3)(CH(2))(m)F homologous systems. Results for CH(3)(CH(2))mF (m=2-5) systems from Meld program at MP2-OPT2/6-311++G(d) level and results for CH(3)(CH(2))mF (m=2-10) systems from Gaussian 98 program at MP2/6-311++G(d)//HF/6-311++G(d) level show that the total correlation energy is a linear function of (m-1), where m is the number of methylene groups in the system.

• 出版日期2009-6
• 单位山东理工大学