Aspirin Desensitization in Patients Undergoing Percutaneous Coronary Interventions With Stent Implantation
- 作者：Roberta Rossini ; Dominick J. Angiolillo ; Giuseppe Musumeci ; PierMario Scuri ; Paolo Invernizzi ; Theodore A. Bass ; Laurian Mihalcsik ; Antonello Gavazzi
- 关键词：Carbon clusters ; Quantum chemistry ; Electronic structure
- 刊名：The American Journal of Cardiology
- 出版年：2008
- 期刊代码：5_00029149
- 类别：med
- 出版时间：15 March 2008
- 卷：101
- 期：6
- 页码：786-789
- 文件大小：63 K
摘要
We present the results of correlated calculations on a variety of small carbon rings. Equilibrium structures and vibrational frequencies are calculated and transition states connecting symmetry-equivalent minima are considered in detail. We show that neither single-reference coupled-cluster nor multiconfigurational self-consistent field methods (even after perturbational inclusion of dynamical correlation effects) give qualitatively correct potential surfaces in the vicinity of the minima, suggesting that there is little recourse for these systems other than a multireference coupled-cluster treatment. Density-functional theory using the B3LYP functional produces results broadly in agreement with single-reference coupled-cluster methods and is thus no more reliable, but considerably more economical.