TY - JOUR
T1 - A density functional theory study for the hydrogen-bonded nucleic acid base pair
T2 - Cytosine dimer
AU - Sahu, Prabhat K.
AU - Mishra, Rama K.
AU - Lee, Shyi Long
PY - 2005/3/31
Y1 - 2005/3/31
N2 - Theoretical investigation for the geometric and energetic properties, rotational constants, harmonic vibrational frequencies, and binding energies of nucleic acid base pair, cytosine dimer, are carried out by using the density functional theory method. The dimer structures resulting from both the keto and the enol (cis/trans) tautomers are investigated in the present study. Various isomers are considered to find the stable structures of the cytosine dimer. The planar cytosine dimer, K-K3 with C 2h symmetry, resulting from nonplanar keto tautomers, is found to be thermodynamically most stable out of the four different stable isomers and having the highest binding energy value, 19.51 kcal/mol (including basis set superposition error correction). The vibrational frequency analysis also suggests a red shift of 367.97 cm -1 for the hydrogen-bonding K-K3 symmetric dimer with two hydrogen bond lengths, each of length 1.913 Å. Moreover, charge distribution (ChelpG charges), Laplacian electronic density distribution, and the dimerization equilibrium for the most stable dimer, K-K3, have also been investigated using the same method and the basis set.
AB - Theoretical investigation for the geometric and energetic properties, rotational constants, harmonic vibrational frequencies, and binding energies of nucleic acid base pair, cytosine dimer, are carried out by using the density functional theory method. The dimer structures resulting from both the keto and the enol (cis/trans) tautomers are investigated in the present study. Various isomers are considered to find the stable structures of the cytosine dimer. The planar cytosine dimer, K-K3 with C 2h symmetry, resulting from nonplanar keto tautomers, is found to be thermodynamically most stable out of the four different stable isomers and having the highest binding energy value, 19.51 kcal/mol (including basis set superposition error correction). The vibrational frequency analysis also suggests a red shift of 367.97 cm -1 for the hydrogen-bonding K-K3 symmetric dimer with two hydrogen bond lengths, each of length 1.913 Å. Moreover, charge distribution (ChelpG charges), Laplacian electronic density distribution, and the dimerization equilibrium for the most stable dimer, K-K3, have also been investigated using the same method and the basis set.
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U2 - 10.1021/jp0459965
DO - 10.1021/jp0459965
M3 - Article
C2 - 16833606
AN - SCOPUS:17144431894
VL - 109
SP - 2887
EP - 2893
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
SN - 1089-5639
IS - 12
ER -