From owner-chemistry@ccl.net Sun Sep 10 10:45:00 2017 From: "Tandon Swetanshu tandons.++.tcd.ie" To: CCL Subject: CCL: Correctly evaluating spin states of a cobalt trimer (using Single Points)? Message-Id: <-52983-170910104322-21501-Dt4223HCrVurql28snQ73A++server.ccl.net> X-Original-From: Tandon Swetanshu Content-Type: multipart/alternative; boundary="f403045f40969b1dba0558d6d488" Date: Sun, 10 Sep 2017 15:43:16 +0100 MIME-Version: 1.0 Sent to CCL by: Tandon Swetanshu [tandons() tcd.ie] --f403045f40969b1dba0558d6d488 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Henrique, For your single point calculations, make sure that you confirm that the wavefunction does not have any instabilities (especially in the case of low spins). Additionally you need to know the temperature at which the X-ray measurement was performed. This is because, the differences in the energies of different spin states is generally quite small. So there is a possibility that, at the temperature at which X-ray measurement was performed, a number of spin states co-exist and the X-ray strucutre, thus, might be a mixture of spin states. Hope that helps. Good luck, Swetanshu. On 10 September 2017 at 13:03, Henrique C. S. Junior henriquecsj+/-gmail.co= m wrote: > Dear colleagues, I=E2=80=99m working with a Cobalt(II) trimer whose molec= ular > structure was achieved by Single Crystal X-Ray Diffraction. My task now i= s > to check the spin states of the structure (High or Low spin). Since Co(II= ) > can have 1 or 3 unpaired electrons, I=E2=80=99m approaching this problem = by > calculating Single Points for every possible multiplicity (10, 8, 6, 4, 2= ) > and assuming that the most stable is the one that represents my structure > (and my spin states). > > Is this approach correct? > > Thank you > > -- > *Henrique C. S. Junior* > > --f403045f40969b1dba0558d6d488 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Henrique,

For you= r single point calculations, make sure that you confirm that the wavefuncti= on does not have any instabilities (especially in the case of low spins).

Additionally you need to know the temperature at whi= ch the X-ray measurement was performed. This is because, the differences in= the energies of different spin states is generally quite small. So there i= s a possibility that, at the temperature at which X-ray measurement was per= formed, a number of spin states co-exist and the X-ray strucutre, thus, mig= ht be a mixture of spin states.

Hope that helps.

= Good luck,
Swetanshu.

On 10 September 2017 at 13:03, Henrique C. S. Junior= henriquecsj+/-gmail.com <owner-che= mistry{=}ccl.net> wrote:

Dear colleagues, I=E2=80=99m working wit= h a Cobalt(II) trimer whose molecular structure was achieved by Single Crys= tal X-Ray Diffraction. My task now is to check the spin states of the struc= ture (High or Low spin). Since Co(II) can have 1 or 3 unpaired electrons, I= =E2=80=99m approaching this problem by calculating Single Points for every = possible multiplicity (10, 8, 6, 4, 2) and assuming that the most stable is= the one that represents my structure (and my spin states).

Is this approach correct?

Thank you


--
Henrique C. S. Junior


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