From laaksone@csc.fi Wed Jan 20 05:31:42 1993 Date: Wed, 20 Jan 1993 05:31:42 +0000 (GMT) From: Leif Laaksonen Subject: Chemistry Gopher server at CSC To: chemistry@ccl.net Message-Id: Thanks to everybody for your interest in our Gopher server at CSC. After my mail to the Comp. Chem. List we could see an increase in the number of connections. However, nobody has sent me any information about interesting ftp archives with good software in chemistry. Does anybody know if the Columbus QC package is still available through ftp. I have been trying to reach the ftp archive for several days without any success. Cheers, -leif laaksonen --------------------------------------------------------- Leif.Laaksonen@csc.fi Center for Scientific Computing P.O. Box 405 SF-02101 Espoo FINLAND Phone: 358 0 4572378 Telefax: 358 0 4572302 Voice Mail: 358 486257407 "In every job to be done there is an element of fun" Mary Poppins --------------------------------------------------------- From haedener@iacrs1.unibe.ch Wed Jan 20 09:39:18 1993 From: haedener@iacrs1.unibe.ch (Konrad Haedener) Message-Id: <9301200739.AA18125@iacrs1.unibe.ch> Subject: Re: proton+electron=neutron? To: CHEMISTRY@ccl.net (CCL) Date: Wed, 20 Jan 1993 08:39:18 +0100 (NFT) Organization: University of Berne, Switzerland Pat Hogue writes: |> |> I hope this isn't the dumbest question this net has ever seen but I havn't |> found the answer yet. What would happen if an elctron and proton were |> brought together at nearly zero kinetic energy: would a high speed |> neutron result or a hydrogen atom? The position-momentum uncertainty relation would probably prevent you from actually performing that experiment in the way you think of it. -- Konrad Haedener Phone: +41 31 65 42 25 Institute for Physical Chemistry FAX: +41 31 65 39 94 University of Berne Switzerland haedener@iacrs1.unibe.ch From oosten@rulhm1.LeidenUniv.nl Wed Jan 20 16:29:22 1993 Date: Wed, 20 Jan 93 15:29:22 +0100 From: oosten@rulhm1.LeidenUniv.nl (A.B. van Oosten) Message-Id: <9301201429.AA04632@rulhm1.LeidenUniv.nl> To: chemistry@ccl.net Subject: Re: proton+electron=neutron? Pat Hogue put the following question : >I hope this isn't the dumbest question this net has ever seen but I havn't >found the answer yet. What would happen if an electron and proton were brought >together at nearly zero kinetic energy: would a high speed neutron result or a >hydrogen atom? The reaction p+ + e- = n as an electromagnetic process is forbidden, or else no atom would be stable. *Weak* conversion of the neutron in a proton + electron produces an additional anti-neutrino. This is considered an expression of lepton number conservation, the lepton numbers of p,e and anti-nu being 0,+1 and -1, respectively. Tony Van Oosten From landman@hal.physics.wayne.edu Wed Jan 20 05:11:36 1993 Date: Wed, 20 Jan 93 10:11:36 EST From: landman@hal.physics.wayne.edu (Joe Landman) Message-Id: <9301201511.AA05932@hal.physics.wayne.edu> To: chemistry@ccl.net Subject: neutron .ne. electron + proton Fellow CCL Readers: I am suprised that no one has noted some importatn features of this reaction. Lepton number is not conserved by P + e => N, but if you have an electron antineutrino + P + e then you can get an N (given enough Energy to create a more massive N (M(N) > M(P) + M(e)), and enough momentum to create the final momentum state. However, bringing a a P + e together with enough force can give rise to an N + electron neutrino (the neutron star formation process). This requires enough energy to create a neutrino with a certain minimum kinetic energy required for momentum conservation (the shape of the spectrum is indicative of this) Now back to the interesting topics, like MD, visulaization, etc (thanks to everyone who sent me info on PC Model) Joe Landman dept of Physics and Astronomy, Wayne State University, Detroit MI landman@hal.physics.wayne.edu From KSEGER@uoft02.utoledo.edu Wed Jan 20 06:20:48 1993 Date: Wed, 20 Jan 1993 10:20:48 -0400 (EDT) From: KSEGER@uoft02.utoledo.edu Subject: density problem To: chemistry@ccl.net Message-Id: <01GTQKVDQ1WY00091E@UOFT02.UTOLEDO.EDU> Netters, I have been working on solvation and discovered this apparent problem. If the box is 18.622 A (making the volume of the box 6457.7158 cubic Angstroms) and there are 216 water molecules in the box, what is the density of the water? I have seen many references to these conditions (TIP3P water is one) and that this is density 1.00 g/cc. The program that I am using calculates this to be density 1.00 g/cc. But by hand (and several persons have checked my work) I get the density to be 0.01 g/cc. I have no doubt that I have been doing the calculations correctly but I wonder if I have misunderstood what is meant by density in solvation. Is this an apparent density which accounts somehow for the solute? (In the problem abovethere is no solute.) Is the density set at 0.01 by convention to reduce the number of waters in the calculation, and because it simulates experiment so well it has become somehow equivalent to density of 1.00? Am I wrong and I did make a mathematical error? I would appreciate help with this as it is the foundaton of a great dealof research I am about to embark upon. Thanks in advance. Kari Seger Cramer email: kseger@uoft02.utoledo.edu Department of Medicinal and Biological Chemistry University of Toledo voice: (419) 537-4028 From SHAUN%JASON.DECNET@relay.the.net Wed Jan 20 04:57:16 1993 Date: 20 Jan 1993 10:57:16 -0600 (CST) From: "Shaun D. Black" Subject: Re: conformational energies of sugars To: chemistry@ccl.net Message-Id: <01GTQLVK6EBM000H1O@nic.the.net> Dear CCLers, The recent discussion of anomeric effects in sugars reminded me of a long-standing curiosity. Perhaps someone 'in the know' would be kind enough to enlighten me. That is, D-glucopyranose is always represented to be the most stable form of glucose (dextrose). However, what about D- glucofuranose? I've done some crude Hudson-type calculations, but was never able to convince myself that the furanose form was not unstable and that it should exist probably; but, I've never seen it described. What's the real story? Enlightenment appreciated. ;-) -Shaun =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= = Shaun D. Black, PhD | Internet: shaun%jason.decnet@relay.the.net = = Dept. of Biochemistry | Keep those cards and letters coming in .... = =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= From rs0thp@RohmHaas.Com Thu Jan 21 45:46:44 1993 From: rs0thp@RohmHaas.Com (Dr. Tom Pierce) Message-Id: <9301201623.AA25346@monte.br.RohmHaas.Com> Subject: A Request on Internet Usage To: chemistry@ccl.net Date: Wed, 20 Jan 1993 11:23:44 +22305823 (EST) Dear Colleagues, My company is studying the whether or not to encourage Internet Access to other researchers(chemists and engineers) beyond the 'high priesthood' of computational chemists in the computer group. So we have a committee, of which I am a member. I have send the following request to a 10 companies (my apologies for this duplication)that I know have an Internet connection. I asked Jan Labanowski if this forum would be appropriate. With his affirmation and requirement that I summarize the responses for the list. If you tell me, I will 'summarize' your responses so that the originators and their organizations will not be identified. ------------------------------------------------------------------- I'm part of a internal team at Rohm and Haas investigating Internet support issues. I'm interested in gathering information on Internet access and usage by other companies, especially other chemical companies. I'd appreciate it if you could spend a few minutes on this and mail it back to me at thpierce@rohmhaas.com or rs0thp@rohvm1 (bitnet). If you have questions or comments you may contact me at: (215)785-8989 (voice/VMX) or thpierce@rohmhaas.com (Internet). Our company is in the process of gathering information on Internet usage by other companies, especially other Chemical/Pharmaceutical companies. o Would you please share your experiences, successes, and usage patterns regarding the Internet? o What are the value-added benefits of using the Internet for your research and business? o How difficult has it been to change your particular corporate or Information Technology / Information Services cultures to embrace this "brave new world" view? -- Sincerely, Thomas Pierce, thpierce@rohmhaas.com or rs0thp@rohvm1 Observation - Network Computing is Computer Slavery. Official Disclaimer:"The opinions expressed are those of the writer and not the Rohm and Haas Company." From root Wed Jan 20 10:57:15 1993 From: Jan Labanowski Date: Wed, 20 Jan 1993 10:55:04 -0500 Message-Id: <199301201555.AA07014@krakow.ccl.net> To: rs0thp@rohmhaas.com Subject: Re: A request and a Question Sorry, Seems like you have resent the message immediately. On the topic... --- Yes, I think it is most appropriate for the CCL If you promissed that you will write a summary of responses, it would be very valuable to people in companies. You see, they need ammunition to fight lawyers who prevent their Internet access "to protect trade secrets" (they forget that anyone can take a diskette home and send it to the world via COMPUSERV, PSI, Inc., friends account in academia or all kinds of freenets. Jan jkl@ccl.net -- Sincerely, Thomas Pierce, thpierce@rohmhaas.com or rs0thp@rohvm1 Observation - Network Computing is Computer Slavery. Official Disclaimer:"The opinions expressed are those of the writer and not the Rohm and Haas Company." From chemistry-request@ccl.net Wed Jan 20 13:02:40 1993 From: slee@hypercom (Thomas Slee) Message-Id: <9301201447.AA10827@hyper.hyper.com> Subject: Re: Anomeric Effect To: chemistry@ccl.net Date: Wed, 20 Jan 1993 09:47:45 -0500 In addition to Dr. Fuchs' extensive list, the review E. Juaristi and G. Cuevas, "Recent Studies of the Anomeric Effect", Tetrahedron, vol 48, pp 5019-5087, 1992 is an extensive and well-referenced review covering many theoretical as well as experimental results. Tom Slee -- Tom Slee Hypercube, Inc., #7-419 Phillip St., Waterloo, Ont. N2L 3X2 Internet: slee@hyper.com Tel. (519) 725-4040 --- Administrivia: This message is automatically appended by the mail exploder. CHEMISTRY@ccl.net --- everyone CHEMISTRY-REQUEST@ccl.net --- coordinator OSCPOST@ccl.net send help from chemistry Anon. ftp www.ccl.net CHEMISTRY-SEARCH@ccl.net --- search the archives, read help.search file first --- From dan@omega.chem.yale.edu Wed Jan 20 11:05:09 1993 From: Dan Severance Message-Id: <9301202105.AA16577@omega.chem.yale.edu> Subject: Re: density... no problem To: chemistry@ccl.net Date: Wed, 20 Jan 93 16:05:09 EST Organization: Laboratory for Computational Chemistry Hi, Just to keep the record straight... The definition of denisty is no different to a modeller than it is to an experimentalist. The density of water is 1.00g/cm^3. > > I have been working on solvation and discovered this apparent > problem. If the box is 18.622 A (making the volume of the box > 6457.7158 cubic Angstroms) and there are 216 water molecules in the > box, what is the density of the water? > > I have seen many references to these conditions (TIP3P water is > one) and that this is density 1.00 g/cc. The program that I am using > calculates this to be density 1.00 g/cc. But by hand (and several > persons have checked my work) I get the density to be 0.01 g/cc. > The density is 1.00... The correct math is as follows: (18.622A)^3 = 6457.7158 A^3 /216 molecules = 29.897 A^3/molecule *6.023x10^23 molecules/mol = 1.8007*10^25 A^3/mol *1.0 mol/18g = 1.0004*10^24 A^3/g *1.0 cm^3/10^24 A^3 = 1.0004 cm^3/g inverting yields the result 0.9996 g/cm^3 Dan Severance dan@omega.chem.yale.edu From SL1HOLL@CUCHEM.bitnet Wed Jan 20 10:44:00 1993 Message-Id: <199301202053.AA06773@oscsunb.ccl.net> Date: Wed, 20 Jan 93 15:44 EST From: Subject: RE: PC Survey RESULTS To: chemistry@ccl.net Dear Netters: Here is the results of the PC survey from a couple of weeks ago. First, I would like to thank everyone who responded to the survey (about 15 of you) your information and comments have been helpful. A brief summary of the results: Most of the people (12/15) responding had academic connections. Most were using 486 machines with SVGA graphics, and as much hard disk as their pocket books would allow. Most people responding would have liked more hard disk and more memory and a math co-processor. This is where the statistical usefulness of this survey ends. There were almost as many different responses to each question as there were people who responded. Please note, some people having multiple PCs at their work place gave comments about more than one PC so the numbers may not tally. The most useful information may be in question # 11, the personal comments, they are quite enlightening. Disclaimer: This data has no statistical value since the population sample was so small with such a diversity of answers. The results presented here shows a large diversity of systems and programs being used for a large variety of functions. ********************************************* The original posting follows: ----------------------------- We are in the process of getting a PC to run/develop chemistry modeling programs and would like to draw on the experience of the viewers of CCL. A survey follows which is an attempt to determine what type of PC's people have, what they are primarily used for, and what their future PC plans are (important for our development goals). As with most things in life we are pressed for time because we would like to get a PC as soon as possible, so I will be collecting responses until next Friday (1/15/93). If sufficient responses are made I will post a summary to the list. Please send all responses to: sl1holl@cuchem If you have already sent your responses, THANK YOU. ******************************************************* Your company: Commercial [ ] Academic [ ] PC Company Manufacturer: Type of Processor: Amount of Memory: Amount of Disk: 1. Are you running DOS? Windows? Version? 2. Is your PC networked? If so, what type of network? 3. What are the main software packages that are used? 4. Which molecular modeling or chemistry packages do you use? 5. Do you run any X-Windows emulator packages? If so, which one(s) and what do you think of it (them)? 6. What type of graphics? Mono, CGA, VGA, SVGA, etc.? 7. How satisfied have you been with your machine(s)? 8. Do you plan to buy more PC's in the future? What type(s)? What type of graphics? 9. What are your PC's mainly used for? 10. Other hardware (Mac's, Workstations, numbers and type of each): 11. Other comments: ************************************************************* PC Survey Results Amt. Comments or Descriptions Company Commercial 1 Academic 12 PC Manufacturer Manufacturer Processor/Speed(MHz)/Memory(MB)/ Hard Disk(MB) Gateway 386DX/ /4/80 Gateway 486/50/16/280 IBM Valuepoint 486/ /8/212 Apple 68030/ /8/80 Dell 386/ /4/60 IBM 286/ /1/30 EPSON 286/ /5/40 FORTE 486/33/16/200 FORTE 486/33 w/EISA/64/1 GB FORTE 386/33/8/120 IBM 286/ /640 KB/20 Zenith 486DX/ /4/80 NCR 486/ /4/80 Comtrade 386/ /4/65 Wyse 386/ /4/170 Unistar Comp. 386SX/ /2/41 Commodore 68030/ /7/280(SCSI) Commodore 68882/ /7/280 HP Vectra 80386/25/4/40 HP Vectra 80387/25/4/40 Korean Make 80286/ /2/40 Ques Amt. 1 DOS 7 Windows 5.5 6 Windows 3.1 6 OS/2 2 2 Networked PC No 5 Yes 9 Type Appletalk 1 Etherlink 1 Ethernet 5 NCSA Telnet 1 System 7.1 (Macs) 1 Windows for Workgroups 1 3 Software Packages Art Expression 1 Excel 3 Fortran 2 Kermit 2 Math Lab 1 Mathcad 2 Mathematica 1 NCSA Telnet 1 Powerpoint 1 Procomm Plus 2 Prowrite 1 Quatropro 1 Sigma Plot 1 Systat 1 TPascal 1 Turbo C++ 1 Vtex 2 Word 5 Wordperfect 3 4 Modeling/ Chemistry ALCHEMY 3 Programs Chem 3D Plus 1 Chem Windows 1 ChemDraft 1 ChemX 1 COSMIC 2.1 1 Elements 1 Hyperchem 2 MOBY 1 Molec 3D 1 MOPAC 6.0 1 Nanovision 1 NITRO 3 PC Model 2 WIMP 2001 1 5 X-Window NO 9 Yes 4 Type NITRO 3 Gfx_Bases X-1 r5 1 6 Graphics EGA 3 CGA 0 VGA 6 SVGA 11 SVGA w/ET 4000 1 Amiga Native 1 7 Satisfied with machine: 386 Machines too slow for most jobs DELL very satisfied, especially 486/ 50 MHz machines Forte little or no problems Gateway speed ok, ISA (16 bits) is bottleneck, very satisfied HP Vectra slow, more disk would be better Unistar very satisfied Zenith like less than Gateway 8 Plan to buy NO 4 Yes 9 What? 486 Machines - 3 responses DELL 486/66 MHz Gateway Mac II's Waiting for 32 bit compiler - 1 response Waiting for 586 and associated software - 1 response 9 PC Main Use Communications 1 Data Collection/Handling 9 Docking 1 Graphics 3 Model Connections 2 Molecular Modeling 4 Terminal Emulation 6 Word Processing 8 10 Other Hardware Apollo DN 4500 2 Convex 1 HP 9000/700 series 2 IBM R/S 6000 10 Macs 83 partial breakdown as given: Classics (32),SX (5), Quadro(12),IIfx (2), IIcx (4),IIsi (1) PC 8 SGI 2 SUN 2 11. Comments: Remember these are personal comments. Buy upgradable machines, look for channel architecture. No use for CPU speed if bus is 1/2 speed Buy LOTS of memory Don't use OS/2 Buy Weitek co-processor to speed calculations (even w/486) Don't buy SX's or 25 MHz (unless for word processing) -------------------------- Consider Macs for modeling due to easier connection to workstations and more versatile than PC's (the person who made the comment has 6 PCs and 25 Macs). Better graphics with Mac. -------------------------- MOBY is a very powerful program -------------------------- PC's are good for personal computing, but not for scientific [translated heavy computing] work. Their floating-point speed is not in the same ballpark as that of high-end workstations. -------------------------- [on an IBM 286 machine] We were very disappointed with fortran using windows, and I think the best way is to develop programs is with X-window emulators (desqview) because it is an opening to the Unix world. -------------------------- Again, thank you for particpating in the survey. Frank Hollinger Columbia University email: sl1holl@cuchem From JSMCM@royal.crc.uno.edu Wed Jan 20 09:47:00 1993 Date: Wed, 20 Jan 1993 15:47 CST From: "JORGE M. SEMINARIO" Subject: Re: density problem To: KSEGER@uoft02.utoledo.edu Message-Id: <01GTQWMZ29MO8Y6BF1@royal.crc.uno.edu> (18gr/mol)*(216) (1cm**3/10**-24 A**3) dens = -------------------------------------------- = 0.99978 gr/cm**3 (6.022*10**23/mol) (6457.7158*A**3) = 1 gr/cm**3 From shepard@dirac.tcg.anl.gov Wed Jan 20 09:50:46 1993 Date: Wed, 20 Jan 93 15:50:46 CST From: shepard@dirac.tcg.anl.gov (Ron Shepard) Message-Id: <9301202150.AA05655@dirac.tcg.anl.gov> To: chemistry@ccl.net Subject: COLUMBUS via anonymous FTP [text deleted] >Does anybody know if the Columbus QC package is still available >through ftp. I have been trying to reach the ftp archive for >several days without any success. > >Cheers, > >-leif laaksonen > >--------------------------------------------------------- >Leif.Laaksonen@csc.fi Yes, the COLUMBUS Program System is available using anonymous FTP. However, the offsite nameservice seems to be misbehaving. If %ftp ftp.tcg.anl.gov does not work for you, then try %ftp 130.202.56.2 BTW, this also holds for Robert Harrison's TCGMSG library. -Ron Shepard shepard@tcg.anl.gov From ryan%phmms0.mms.smithkline.com@smithkline.com Wed Jan 20 11:50:46 1993 Date: Wed, 20 Jan 93 16:50:46 -0500 From: ryan%phmms0.mms.smithkline.com@smithkline.com (Dominic Ryan) Message-Id: <9301202150.AA23609@phmms0.mms.smithkline.com> To: chemistry@ccl.net Subject: Density The following calculation results in just about 1.0 g/cc: number of H2O in 1cc: 216 / 6457.7158 * 10**24 i.e. #H2O/ang**3 * 10**24ang**3 weight per h20: 18 / 6.022*10**23 density = #h2O_per_cc * weight_per_H2O: 216 * 10**24 * 18 -------------------------- = 0.99979 g/cc 6457.7158 * 6.022 * 10**23 M. Dominic Ryan SmithKline Beecham Pharmaceuticals (215)-270-6529 internet: ryan%phmms0.mms@smithkline.com From JSMCM@royal.crc.uno.edu Wed Jan 20 10:01:00 1993 Date: Wed, 20 Jan 1993 16:01 CST From: "JORGE M. SEMINARIO" Subject: density problem (correction) To: KSEGER@uoft02.utoledo.edu Message-Id: <01GTQX4YKI808Y6BF1@royal.crc.uno.edu> (18gr/mol)*(216water) (1A**3/10**-24 cm**3) dens= -------------------------------------------- = 0.99978 gr/cm**3 (6.022*10**23 water/mol) (6457.7158*A**3) = 1 gr/cm**3 From sliu@sugar.ps.uci.edu Wed Jan 20 06:34:00 1993 Message-Id: <9301202234.AA19980@sugar.ps.uci.edu> To: chemistry@ccl.net Subject: A good program to show 3D on a Mac Date: Wed, 20 Jan 93 14:34:00 -0800 From: sliu@sugar.ps.uci.edu Dear Netter : Does anyone know any program that reads PDB files and display 3D on the Mac ? It would be wonderful if it allows the user to rotate the molecule and it also exports Postscript files. If you happen to know it please do tell me. Thanks! Song Liu Chemistry, Univ. of CA, Irvine CA 92717 From fisher@scripps.edu Wed Jan 20 07:20:27 1993 Date: Wed, 20 Jan 93 15:20:27 PST From: fisher@scripps.edu (Cindy Fisher) Message-Id: <9301202320.AA19562@crystal.Scripps.EDU> To: chemistry@ccl.net Subject: Re: density problem Kari, I did the calculation quickly and came up with a density of 1.00 g/cm**3. 216 molecules water * (1 mol/6.02*10**23 molecules) * (18g water/mol) --------------------------------------------------------------------- (18.622*10**(-8))**3 cm**3 = 1.00 g/cm**3 So embark away! Cindy Fisher =========================================================================== Cindy Fisher Department of Molecular Biology--MB4 The Scripps Research Institute 10666 North Torrey Pines Road La Jolla, CA 92037 E-mail to: fisher@scripps.edu From jbharris@tenet.edu Wed Jan 20 15:18:32 1993 Date: Wed, 20 Jan 1993 21:18:32 -0600 (CST) From: Judith Harris Subject: Volunteers Needed for On-Line Educational Project To: BIOCIS-L@sivm.bitnet, BIOMED-L@mcgill1.bitnet, BIOMED-L@ndsuvm1.bitnet, Message-Id: WOULD YOU BE WILLING TO SHARE WHAT YOU KNOW WITH PRE-COLLEGE STUDENTS AND TEACHERS BY ELECTRONIC MAIL? Recent estimates indicate that there are now more than 50,000 classroom teachers from primary, middle, and secondary schools who hold accounts on the Internet. This makes a very special kind of learning available to them: one which directly involves subject matter experts communicating with students and teachers about their specialties, via electronic mail. With support from the Texas Center for Educational Technology, we (at the University of Texas at Austin) are now piloting a new Internet-based service (the "Electronic Emissary") that will bring together pre- college students, their teachers, and subject matter experts (SMEs) electronically, helping them to create telecomputing exchanges centered around the students' learning in the SMEs' disciplines. For example, * A class studying South America could learn about recent global environmental research results from a scientist who studies rainforest deforestation in Brazil. * A class studying geometry might "talk" electronically with Euclid, who is actually a mathematics professor. * A class studying the future of education might converse with an emerging technologies specialist from California's Silicon Valley. * A class studying American History might electronically interview Harry Truman, who is really a curator with the National Archives. * A class exploring the rapidly-changing governmental structures that are emerging in what was once the Soviet Union might correspond with a group of graduate political science students at a university in the CIS. * Or, a class reading _Huckleberry Finn_ might correspond with an African-American studies scholar about the repercussions resulting from the enacting of the Emancipation Proclamation. In this pilot phase of the project, 10-12 SMEs or SME groups are needed to correspond regularly (approximately 4 times per week) with primary, middle school, or secondary students and their teachers (1 SME or expert group per class). Each electronic exchange will begin with 2 weeks of project planning via electronic mail between the SMEs and the teachers (2/16 - 2/28/93). Communications with students will begin during the week of March 1st, and will continue for 4 - 6 weeks. ==> If you would like to find out more about this pilot ==> project, please send electronic mail to Judi Harris, ==> jbharris@tenet.edu. Please include your name, ==> institution, and areas of expertise. ==> PLEASE RESPOND ASAP; all teacher-SME pairs will be ==> formed by 2/15/93. @>--;-- Judi Harris _ /| _^^_ Department of Curriculum & Instruction \'o.o'( \ University of Texas at Austin =(___)= ( ) c.." ..cc--"\_? Internet address: JBHarris@Tenet.edu c./ @>--;-- From mail Wed Jan 20 18:39:49 1993 From: hyper!slee (Thomas Slee) Message-Id: <9301202138.AA00520@hyper.hyper.com> Subject: Re: density problem To: chemistry@ccl.net Date: Wed, 20 Jan 1993 16:38:18 -0500 > Netters, > I have been working on solvation and discovered this apparent problem. >If the box is 18.622 A (making the volume of the box 6457.7158 cubic Angstroms) >and there are 216 water molecules in the box, what is the density of the water? > > I have seen many references to these conditions (TIP3P water is one) >and that this is density 1.00 g/cc. The program that I am using calculates this >to be density 1.00 g/cc. But by hand (and several persons have checked my work) >I get the density to be 0.01 g/cc. > Sorry, but my calculation goes like this: Mass of water molecules = 18(g/mol) * (216/6.023e23)mol = 6.455e-21 g Volume = (18.622e-8)^3 cm3 = 6.458e-21 cm3 Density = M/V = 0.9996 g/cm3. Tom Slee -- Tom Slee Hypercube, Inc., #7-419 Phillip St., Waterloo, Ont. N2L 3X2 Internet: slee@hyper.com Tel. (519) 725-4040