<html><head></head><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:16px"><div id="yui_3_16_0_ym19_1_1490937962977_2603">Hello and greetings</div><div dir="ltr" id="yui_3_16_0_ym19_1_1490937962977_4022">i am simulating my protein in implicit solvent. the protein has ca2+ ion in it. the gbsa.itp file doesn't have parameters for any ion.</div><div id="yui_3_16_0_ym19_1_1490937962977_4082" dir="ltr">how can i add parameters of my ion?</div><div id="yui_3_16_0_ym19_1_1490937962977_4090" dir="ltr">As mentioned in tutorial.....</div><div id="yui_3_16_0_ym19_1_1490937962977_4156" dir="ltr">[ implicit_<span id="yui_3_16_0_ym19_1_1490937962977_4184">genborn</span>_params ]</div><div id="yui_3_16_0_ym19_1_1490937962977_4212" data-canvas-width="448.317" style="left: 165.355px; top: 187.344px; font-size: 16.6043px; font-family: monospace; transform: scaleX(0.99626);">;Atomtype sar st pi gbr hct</div><div id="yui_3_16_0_ym19_1_1490937962977_4213" data-canvas-width="498.1299999999998" style="left: 165.355px; top: 207.269px; font-size: 16.6043px; font-family: monospace; transform: scaleX(0.99626);"><div id="yui_3_16_0_ym19_1_1490937962977_4214" dir="ltr"><br></div></div><div id="yui_3_16_0_ym19_1_1490937962977_4157" dir="ltr">Values in columns 1-3 are not currently used. Column 4 contains the atomic van der Waals radii, which are used in computing the Born radii. <br></div><div id="yui_3_16_0_ym19_1_1490937962977_4238" dir="ltr">the van der Waals radii of ca2+ is 0.231? is it right? or how can i calculate the hct?</div><div id="yui_3_16_0_ym19_1_1490937962977_4320" dir="ltr">thank you<br></div></div></body></html>