The phenyl cation 1 has been prepared by co-deposition of iodobenzene 6 or bromobenzene 7 with a microwave-induced argon plasma and characterized by IR spectroscopy in cryogenic argon matrices. The cation can clearly be identified by its strongest absorption at 3110 cm-1 that is rapidly bleached upon visible light irradiation. This characteristic band is observed neither in the conventional photochemistry
                                    苯基阳离子1是通过将
碘苯6或
溴苯7与微波诱导的
氩等离子体共沉积而制备的,并通过红外光谱法在低温
氩基质中进行表征。阳离子可以通过在3110 cm - 1处最强的吸收来清楚地识别,该吸收在可见光照射下会迅速漂白。在常规的6或7光
化学中,或在使用烷基卤或
氯苯的放电实验中均未观察到该特征谱带。后一个发现与精力充沛的考虑相符。根据密度泛函理论(DFT)计算,最强吸收1是由CH-H拉伸振动引起的,该振动几乎全部涉及原氢。同位素标记实验证实了这一点。卤代苯/ N 2混合物的共沉积导致3110 cm - 1吸收率降低,而在2200-2400 cm - 1的红外光谱范围内检测到一些新信号。包含1%和1%N 2的基质的退火会导致分配给苯重氮离子2的2260 cm - 1处的宽带增加。2327 cm - 1处清晰的信号先前已经分配给的N-N伸缩振动2是由于分子氮。尚不清楚触发N 2的IR活性的机制。对包含1%和0