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<body class='hmmessage'><div dir='ltr'>Hi<div><br></div><div>We are studying an organo-metallic compound which contains 3 Benzene rings, phosphorous, oxygen, Iodine, and rhenium atoms.</div><div>Our quantum chemistry study using B3LYP/6-31+G* (Gaussian basis set) shows that the ground state of the system is singlet (spin -unpolarized). We attempted to optimize this structure using quantum espresso to calculate some other electronic properties. Then surprisingly we found that the spin-polarized system is more stable than the spin-unpolarized one in contrast with our quantum chemistry study. In the following you can see my input file and I wonder whether there is something wrong in the input that made the very noticeable contrast. I appreciate your comments to understand the issue and solve it in advance. </div><div><br></div><div>q/e input:</div><div>&control</div><div> calculation='relax',</div><div> restart_mode='from_scratch',</div><div> prefix='Re-Be',</div><div> pseudo_dir = './pseudo/',</div><div> outdir='./tmp/',</div><div> tprnfor=.t. ,</div><div> etot_conv_thr=1.0D-4,</div><div> forc_conv_thr=1.0D-3,</div><div> nstep=300,</div><div> dt=10,</div><div> /</div><div> &system</div><div> ibrav= 8, a=20, b=20, c=20, nat=37, ntyp=6,</div><div> ecutwfc = 30, ecutrho = 300, occupations='smearing', smearing='marzari-vanderbilt', degauss=0.005,</div><div> nspin=2 , starting_magnetization(1)=1 ,starting_magnetization(2)=1 , starting_magnetization(3)=1 , starting_magnetization(4)=1 , starting_magnetization(5)=1 , starting_magnetization(6)=1 ,</div><div> /</div><div> &electrons</div><div> conv_thr = 1.0d-6,</div><div> mixing_beta=0.2,</div><div> mixing_mode=local-TF,</div><div><span style="font-size: 12pt;"> /</span></div><div> &IONS</div><div> ion_dynamics="bfgs",</div><div> upscale=100.0D0 ,</div><div>/</div><div>ATOMIC_SPECIES</div><div>Re 186.207 Re.pbe-hgh.UPF</div><div>O 15.999 O.pbe-rrkjus.UPF</div><div>C 12.000 C.pbe-rrkjus.UPF</div><div>H 1.000 H.pbe-rrkjus.UPF</div><div>I 126.90 I.pbe-n-rrkjus_psl.0.2.UPF</div><div>P 30.9737 P.pbe-n-van.UPF</div><div><span style="font-size: 12pt;">K_POINTS {gamma}</span> <br><br><div style="line-height:21px;color:rgb(68, 68, 68);font-size:15px;"><h5 style="font-size:15px;font-weight:normal;padding:0px;border:0px;"><font color="#333333" face="verdana, tahoma" size="2" style="line-height:normal;"><span style="line-height:19px;">-------------------------------------------------</span></font></h5><div><font color="#333333" face="verdana, tahoma" size="2" style="line-height:normal;"><span style="line-height:19px;">Alex Granov</span></font></div><h5 style="font-size:15px;font-weight:normal;padding:0px;border:0px;"><font color="#333333" face="verdana, tahoma" style="line-height:normal;"><span style="line-height:19px;"><font size="2" style="line-height:normal;">Московский физико-технический институт </font><font size="1" style="line-height:normal;">(</font></span></font><span style="line-height:1.5;color:rgb(51, 51, 51);font-family:verdana, tahoma;"><font size="1" style="line-height:normal;">MIPT)</font></span></h5></div><div style="line-height:21px;color:rgb(68, 68, 68);font-size:15px;"><h5 style="line-height:1.5;font-size:15px;font-weight:normal;padding:0px;border:0px;font-family:verdana, tahoma;color:rgb(51, 51, 51);"><font size="2" style="line-height:normal;">Moscow, Russia</font></h5></div></div> </div></body>
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