ENERGETICS OF THE INTERACTION BETWEEN WATER, MEMBRANES AND MACROMOLECULES

我们已经确定了水合热力学， _Ho298、_So298和_Go298，用于单烷基 铵离子，C1-C8和1-3 C1，使用电喷雾 电离平衡气相离子分子反应。的 水化热力学值由平衡计算 在离子源水部分条件下测定的常数 压力范围在0和100 m3之间，相当于0-1%的 总源压力和离子源温度范围在 23和85 oC。我们的研究清楚地表明，1）添加第一个 水对裸离子的放热明显大于添加 第三; 2）将第一水加入到单烷基铵中， 离子是约2千卡/摩尔更有利的情况下， 单甲基比单丁基，并且存在相对少的 通过进一步增加烷基链长度而改变; 3）添加 第一水与一甲基铵离子的比率为约3千卡/摩尔 对于三甲基的情况更有利。此外，添加 第一水与丙基铵的比率为约1.5千卡/摩尔以上 比将第一水加入到三甲基 铵

We have determined hydration thermodynamics, _Ho298, _So298, and _Go298, for a family of monoalkyl ammonium ions, C1-C8 and 1-3 C1, using the electrospray ionization-equilibrium gas phase ion molecule reactions. The hydration thermodynamic values were calculated from equilibrium constants measured under conditions of ion source water partial pressures ranging between 0 and 100 mtorr, equivalent to 0-1% of total source pressure, and ion source temperatures ranging between 23 and 85oC. Our study clearly shows that 1) addition of the first water to a bare ion is apprecibly more exothermic than addition of the third; 2) addition of the first water to monoalkyl ammonium ions is about 2 kcal/mole more favorable for the case of monomethyl than for monobutyl and that there is relatively little change by further increases of alkyl chain length; 3) addition of the first water to monomethyl ammonium ions is about 3 kcal/mole more favorable for the case of trimethyl. Furthermore, addition of the first water to propyl ammonium is about 1.5 kcal/mole more favorable than the addition of the first water to trimethyl ammonium