From carolina@ce.ifisicam.unam.mx Fri Aug 20 16:37:21 1993 Received: from ce.ifisicam.unam.mx.ifisicam.unam.mx (ce.ifisicam.unam.mx) for carolina@ce.ifisicam.unam.mx by oscsunb.ccl.net (5.65c+KVa/930601.1506) id AA09837; Fri, 20 Aug 1993 23:37:49 -0400 Message-Id: <199308210337.AA09837@oscsunb.ccl.net> Received: by ce.ifisicam.unam.mx (16.7/16.2) id AA17194; Fri, 20 Aug 93 21:37:22 -0500 From: Carolina Subject: Question on ionization potentials. To: CHEMISTRY@ccl.net (SEND_NEWS) Date: Fri, 20 Aug 93 21:37:21 CDT Mailer: Elm [revision: 70.30] Dear netters: I am doing my summer proyect and I came along with something that I can not understand. I have calculated with a semiempirical method a few molecular properties, such as charges, ionization potentials and frontier orbitals of some molecules. The set of molecules I have worked on are neutral, but can also be calculated as charged species, since they contain several sulfate or phosphate groups. The neutral species have ionization potentials about -10 eV, those moderately charged have ionization potentials about -0.05 eV, but fully charged molecules give me ionization potentials of +20 eV if I follow Koopman's theorem. I know that neutral species of these molecules exist since I have a sample in my hands now, and I know that partially charged molecules also exist since I can tritrate them, but .... This is my question since I am not a theoretician!!! Could the fully charged molecules exists at all?. If am correct the ionization potential predicts that they won't. Any comments will be wellcome, since they will help me to write my report. With many thanks, -- ___________________________________________________________________ CAROLINA GODOY-ALCANTAR Facultad de Ciencias Universidad del Edo. de Morelos Chamilpa, Morelos. Mexico email: carolina@ifisicam.unam.mx From ipcakc@vigyan.ernet.in Wed Aug 21 15:00:33 1993 Received: from relay2.UU.NET for ipcakc@vigyan.ernet.in by oscsunb.ccl.net (5.65c+KVa/930601.1506) id AA19728; Sat, 21 Aug 1993 13:30:22 -0400 Received: from spool.uu.net (via LOCALHOST) by relay2.UU.NET with SMTP (5.61/UUNET-internet-primary) id AA09366; Sat, 21 Aug 93 13:30:21 -0400 Received: from sangam.UUCP by uucp5.uu.net with UUCP/RMAIL (queueing-rmail) id 132850.27971; Sat, 21 Aug 1993 13:28:50 EDT Received: from vigyan.UUCP by sangam.ncst.ernet.in (4.1/SMI-4.2-ERNET-relay) with UUCP id AA24435; Sat, 21 Aug 93 22:45:19+0530 Received: by iisc.ernet.in (ERNET-IISc/AT&T UNIX SYS V.3.2) id AA10032; Sat, 21 Aug 93 21:03:25 EDT Received: by vigyan.iisc.ernet.in (smail2.3) id AA24504; 21 Aug 93 20:00:33 EST (Sat) To: CHEMISTRY@ccl.net Subject: M.S.Gordon Date: 21 Aug 93 20:00:33 EST (Sat) From: ipcakc@vigyan.iisc.ernet.in Message-Id: <9308212000.AA24504@vigyan.iisc.ernet.in> Hi, does anybody know the e-mail of prof. M.S. Gordon? D.Sengupta IISc bangalore India ipcakc@ipc.iisc.ernet.in From mgauss@alchemy.chem.utoronto.ca Sat Aug 21 11:40:40 1993 Received: from alchemy.chem.utoronto.ca for mgauss@alchemy.chem.utoronto.ca by oscsunb.ccl.net (5.65c+KVa/930601.1506) id AA21269; Sat, 21 Aug 1993 15:44:37 -0400 Received: by alchemy.chem.utoronto.ca (5.65/1.34) id AA23735; Sat, 21 Aug 93 15:40:40 -0400 Date: Sat, 21 Aug 93 15:40:40 -0400 From: mgauss@alchemy.chem.utoronto.ca (Mike Peterson / Monstergauss) Message-Id: <9308211940.AA23735@alchemy.chem.utoronto.ca> To: chemistry@ccl.net Subject: MOPAC 93 open shell calculations I am trying to verify that MOPAC 93 runs properly on my HP system, and I can't get an open shell doublet job to run: AM1 TS alpha, beta-unsat acid from george@gravity.cray.com (George Fitzgerald) carboxyl radical for decarboxylation (correct answer is 3.19 Kcal) C 0.0000000 0 0.000000 0 0.000000 0 0 0 0 0.3262 O 1.2235372 1 0.000000 0 0.000000 0 1 0 0 -0.2483 O 1.2372997 1 118.704508 1 0.000000 0 1 2 0 -0.3070 C 2.1148597 1 157.902093 1 -174.337130 1 1 2 3 -0.0873 C 1.3006401 1 121.439811 1 -174.074926 1 4 1 3 -0.2313 H 1.0750946 1 98.120631 1 6.535395 1 4 1 3 0.2176 H 1.1001354 1 122.939376 1 2.612134 1 5 4 6 0.1720 H 1.1027606 1 120.905097 1 -178.797410 1 5 4 6 0.1580 I have tried putting "DOUBLET" on the command line, which was used on MOPAC 6.0 - MOPAC 6.0 doesn't care whether it is given or not (I works both ways), and neither does MOPAC 93 (fails both ways right after printing the distance matrix) with: HESSIAN CALCULATED NUMERICALLY C.I. IS OF SIZE LESS THAN ROOT SPECIFIED MODIFY SIZE OF C.I. OR ROOT NUMBER Any hints/clues appreciated, since it looks like all open shell jobs will now fail. I have read Section 8.5.8 on the changes in the C.I. keywords, but DOUBLET states aren't mentioned there. [I never really used MOPAC 6 open shells, and don't really know what exactly MOPAC did (or now does) for open shells.] Mike.