From owner-chemistry@ccl.net Mon Dec 18 10:47:00 2017 From: "Grigoriy Zhurko reg_zhurko||chemcraftprog.com" To: CCL Subject: CCL:G: Combining Z-matrix with Cartesian coordinates in Gaussian Message-Id: <-53092-171218102740-11818-Z5L9q2Ab7haDw7EwiycUYw|*|server.ccl.net> X-Original-From: Grigoriy Zhurko Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Date: Mon, 18 Dec 2017 18:34:10 +0400 MIME-Version: 1.0 Sent to CCL by: Grigoriy Zhurko [reg_zhurko]~[chemcraftprog.com] Hello, I need to perform a PES scan in Gaussian, so that the distance between an atom and the center between two other atoms will be scanned. When I need to simply scan an iteratomic distance, I use OPT(MODREDUNDANT). But in current case I have to use a z-matrix and add a dummy atom (the center between two real atoms). It is possible to use only Z-matrix for this job, but the result becomes rather bad: the optimization starts with evident bugs (probably because this geometry has rings). I tried to combine the Z-matrix with the Cartesians. I created the following input file: %NPROCSHARED=3 #P uwB97XD/6-31G(D,P) OPT(Z-Matrix,LOOSE) NOSYMM Silicon 0 1 X N 1 R12 X 1 1.400000 2 90.000000 N 1 R12 3 90.000000 2 180.000000 N 1 R15 2 A215 3 -90.000000 N 1 R16 3 A316 5 D5316 Zn 1 R17 2 A217 5 -D5217 6 0.000000000 2.863016000 1.101006000 6 0.000000000 2.425840000 2.425840000 6 0.000000000 1.101006000 2.863016000 1 0.000000000 3.193595000 3.193595000 6 0.000000000 2.863016000 -1.101006000 6 0.000000000 2.425840000 -2.425840000 6 0.000000000 1.101006000 -2.863016000 1 0.000000000 3.193595000 -3.193595000 6 0.000000000 -1.101006000 -2.863016000 6 0.000000000 -2.425840000 -2.425840000 6 0.000000000 -2.863016000 -1.101006000 1 0.000000000 -3.193595000 -3.193595000 6 0.000000000 -2.863016000 1.101006000 6 0.000000000 -2.425840000 2.425840000 6 0.000000000 -1.101006000 2.863016000 1 0.000000000 -3.193595000 3.193595000 6 0.000000000 -4.245855000 0.681548000 6 0.000000000 -4.245855000 -0.681548000 6 0.000000000 -0.681548000 -4.245855000 6 0.000000000 0.681548000 -4.245855000 6 0.000000000 -0.681548000 4.245855000 6 0.000000000 0.681548000 4.245855000 6 0.000000000 4.245855000 0.681548000 6 0.000000000 4.245855000 -0.681548000 1 0.000000000 -5.096481000 1.350466000 1 0.000000000 -5.096481000 -1.350466000 1 0.000000000 -1.350466000 -5.096481000 1 0.000000000 1.350466000 -5.096481000 1 0.000000000 5.096481000 -1.350466000 1 0.000000000 5.096481000 1.350466000 1 0.000000000 -1.350466000 5.096481000 1 0.000000000 1.350466000 5.096481000 Variables: R12 = 2.04198300 R15 = 2.04198300 A215 = 90.00000000 R16 = 2.04198300 A316 = 90.00000000 D5316 = 180.00000000 A217 = 90.00000000 D5217 = 90.00000000 constants R17 = 0.40000000 s 20 0.2 This job constructs a valid geometry, the optimization starts, but it starts incorrectly: during the optimization, only the Z-matrix parameters are varied, while the coordinates of most atoms are fixed. Can I do something to make Gaussian optimize these atomic coordinates as well? From owner-chemistry@ccl.net Mon Dec 18 13:08:01 2017 From: "Gabriele Mogni gabriele.mogni .. gmail.com" To: CCL Subject: CCL: Please join these Computational Science groups on Facebook and LinkedI Message-Id: <-53093-171218130647-28250-Sb0z10isbJNNpKi+3zOBrw]=[server.ccl.net> X-Original-From: "Gabriele Mogni" Date: Mon, 18 Dec 2017 13:06:45 -0500 Sent to CCL by: "Gabriele Mogni" [gabriele.mogni,+,gmail.com] Dear CCL.net community members, Please join my Computational Science social network groups on Facebook and LinkedIn: https://www.facebook.com/groups/compscieng/ https://www.linkedin.com/groups/13506531 These groups have grown a lot since last year and they now include many interesting announcements on conferences, job offers, codes, news articles and much more material which is relevant to all branches of computational science and engineering, including of course computational chemistry. Many thanks for your support, and Merry Christmas to you all! Dr. Gabriele Mogni (UPMC, Paris, France)