Paixão J A, Matos Beja A, Ramos Silva M, Alte Da Veiga L, Serra A C
Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, P-3000 Coimbra, Portugal.
Acta Crystallogr C. 2000 Nov;56 Pt 11:1348-50. doi: 10.1107/s0108270100010441.
The title compound, C(7)H(6)O(2), forms infinite chains where the molecules are hydrogen bonded via the hydroxyl and aldehyde groups, with an O.O distance of 2.719 (3) A. Interchain interactions are weak. The geometry of the ring differs from the ideal form due to the effect of the substituents. Ab initio (Hartree-Fock self-consistent field-molecular orbital and density functional theory) calculations for the free molecule reproduce well the observed small distortions of the ring. In the crystal, the geometry deviates from the ideal C(s) symmetry of the free molecule, as given by the ab initio calculations. The aldehyde and hydroxyl groups are twisted around the single bonds which join them to the ring as a result of the intermolecular hydrogen-bond interactions. These are also responsible for an elongation of the hydroxy C-OH bond compared with that calculated for the free molecule.
标题化合物C₇H₆O₂形成无限链，其中分子通过羟基和醛基形成氢键，O…O距离为2.719(3) Å。链间相互作用较弱。由于取代基的影响，环的几何形状不同于理想形式。对游离分子进行的从头算（哈特里-福克自洽场-分子轨道和密度泛函理论）计算很好地再现了观察到的环的小畸变。在晶体中，几何形状偏离了从头算计算得出的游离分子的理想Cₛ对称性。由于分子间氢键相互作用，醛基和羟基围绕将它们连接到环上的单键发生扭曲。这些还导致羟基C-OH键相比于游离分子的计算值有所伸长。
