Cation-cation contact pairing in water: guanidinium.
نویسندگان
چکیده
The formation of like-charge guanidinium-guanidinium contact ion pairs in water is evidenced and characterized by X-ray absorption spectroscopy and first-principles spectral simulations based on molecular dynamics sampling. Observed concentration-induced nitrogen K-edge resonance shifts result from π* state mixing and the release of water molecules from each first solvation sphere as two solvated guanidinium ions associate into a stacked pair configuration. Possible biological implications of this counterintuitive cation-cation pairing are discussed.
منابع مشابه
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ورودعنوان ژورنال:
- The Journal of chemical physics
دوره 139 3 شماره
صفحات -
تاریخ انتشار 2013