Breakdown of the adiabatic approximation in trans-polyacetylene
Breakdown of the adiabatic approximation in trans-polyacetylene
复制标题
反式聚乙炔中绝热近似的分解
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
M. Lavrentiev
中科院分区：
文献类型：
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作者：
W. Barford;R. Bursill;M. Lavrentiev
我们用密度矩阵重整化群方法求解了一个相互作用电子与纵向声子耦合的模型。该模型是参数化的反式聚乙炔。我们计算了基态和第一激发奇宇称单重态和三重态。我们调查他们的能量和几何多达102个网站。当链长大于经典孤子尺寸时，三重态的跃迁能和孤子宽度与绝热近似有很大的偏差。相反，单重态的跃迁能接近绝热预测。
We solve a model of interacting electrons coupled to longitudinal phonons using the density matrix renormalization group method. The model is parametrized for trans-polyacetylene. We calculate the ground state and first excited odd-parity singlet and triplet states. We investigate their energies and geometries for up to 102 sites. The transition energy and the soliton width of the triplet state show significant deviations from the adiabatic approximation for chain lengths larger than the classical soliton size. In contrast, the transition energy of the singlet is close to the adiabatic prediction.