TY - JOUR AU - Brynda, M. AU - Berclaz, T. AU - Geoffroy, M. TI - Intramolecular motion in dibenzobarrelenephosphinyl radical: A single crystal EPR study at variable temperature PY - 2000 JF - Chemical Physics Letters JA - Chem. Phys. Lett. SN - 0009-2614 VL - 323 SP - 474 EP - 481 L1 - http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TFN-40HTWJT-H-M&_cdi=5231&_orig=search&_coverDate=06%2F23%2F2000&_qd=1&_sk=996769994&wchp=dGLSzS-lSzBk&_acct=C000043220&_version=1&_userid=779890&md5=a7f86e59dc2a8a1885f54b8cb4ecdf58&ie=f.pdf L2 - http://www.sciencedirect.com/science?_ob=ArticleURL&_aset=W-WA-A-A-A-MsSAYVW-UUA-AUZVZZEVBB-YUVADVW-A-U&_rdoc=1&_fmt=full&_udi=B6TFN-40HTWJT-H&_coverDate=06%2F23%2F2000&_cdi=5231&_orig=search&_st=13&_sort=d&view=c&_acct=C000043220&_version=1&_urlVersion=0&_userid=779890&md5=03e5ddb2c92f47a85d2fa82153a2ad79 L3 - http://www.sciencedirect.com/science?_ob=ArticleURL&_aset=W-WA-A-A-A-MsSAYVW-UUA-AUZVZZEVBB-YUVADVW-A-U&_rdoc=1&_fmt=summary&_udi=B6TFN-40HTWJT-H&_coverDate=06%2F23%2F2000&_cdi=5231&_orig=search&_st=13&_sort=d&view=c&_acct=C000043220&_version=1&_urlVersion=0&_userid=779890&md5=241d2724833313d2fcd67266d40e1ab5 M3 - 10.1016/S0009-2614(00)00525-X UR - http://dx.doi.org/10.1016/S0009-2614(00)00525-X N2 - The g, 31P and 1H hyperfine tensors of the dibenzobarrelene phosphinyl radical, trapped in an X-irradiated single crystal of dibenzobarrelene phosphine, were estimated at 45 and 300 K. They indicate that among the three locations of the phosphinyl hydrogen expected from DFT calculations, only two are occupied at 40 K and that the third one remains practically vacant, even at 300 K. The temperature dependence of the EPR spectrum was simulated by assuming jumps between two P–H bond orientations (energy barrier ~= 0.5 kcal mol−1) which correspond to the conformation of the PH2 moiety in the only rotamer present in the dibenzobarrelene phosphine crystal. ID - 49 ER -